- Introduction
- Flooding and Topology Basics
- Link Flooding Issues
- Topology problems
- Other flooding-related issues
- Other topology-related issues
Introduction
This document provides hints, tips and how-to information on debugging MPLS-TE issues related to the topology and flooding TE information between routers. This is intended to assist users with debugging such issues in their own networks, and to help ensure that appropriate diagnostic information is provided to Cisco should support be required.
Terminology
The following terms are used throughout this document:
- LSA: Link-State Advertisement. This is well-known to engineers running OSPF networks, but in IS-IS the term LSP (Link-State PDU) is correct for the equivalent object. LSA is used here for both protocols to avoid confustion with TE Label-Switched Paths.
- TE showtech: the output of "show tech-support mpls traffic-eng"
- IGP showtech: the output of "show tech-support isis" or "show tech-support isis", depending on the IGP in use.
- PFI showtech: the output of "show tech-support pfi"
- RSI showtech: the output of "show tech-support rsi" and "show tech-support srlg"
Note that all showtechs must be collected while logged in as a user with cisco-support privileges, or critical information will not be present.
Flooding and Topology Basics
Data Flow in IOS-XR
In IOS-XR, the TE control process and the IGPs (OSPF and IS-IS) are separate, and maintain their own copies of data they require. Under normal operation, the usual flow of information and data between TE and the IGPs is:
- The IGP tells TE which adjacencies are up for each area. TE is not aware of adjacencies that are not fully established.
- TE generates a local LSA to be flooded into each area
- The IGP floods the local LSA into the topology on TE's behalf
- The IGP passes all TE topology information it receives from all nodes in the network to TE, including the information generated by the local TE process
- TE uses this topology to calculate tunnel paths
Understanding this data flow is essential to accurate diagnosis of flooding and topology issues. It's also very helpful when requesting support from Cisco if the problem has already been isolated as far as possible; this decreases the time it takes for issues to reach the appropriate team.
Please note that this page is arranged in order of this data flow. However, when debugging an issue it's more usual to work backwards. As an example:
- we notice that a tunnel is down
- we discover this is because an address on its path isn't in the topology
- this in turn is because the link isn't flooded
- the link isn't flooded because the interface is down.
There's no reason to use this page in the order it's written if that's what works for you!
Show commands
There are a number of show commands which are very important in the investigation of flooding and topology problems, so it's a good idea to be familiar with them. These are:
- General:
- show mpls traffic-eng igp-areas gives general information about the IGP instances and areas that are known to TE
- Interface/neighbor data
- show ospf neighbor displays the OSPF adjacencies which exist
- show isis neighbors and show isis adjacency give information about IS-IS adjacencies.
- show mpls traffic-eng link-management interfaces gives information about the state of each link known to TE.
- show mpls traffic-eng link-management igp-neighbors displays what TE knows about each IGP-neighbor
- Status of local LSA
- show mpls traffic-eng link-management advertisements displays the local LSA that TE has flooded to each IGP-area.
- show isis mpls traffic-eng advertisements displays the local LSA that ISIS has flooded to each of its areas
- show ospf mpls traffic-eng link displays the local-LSA data that OSPF has received from TE, and show ospf mpls traffic-eng fragment shows the LSA fragments that are being flooded to the network
- Complete topology
- show isis database verbose displays the topology in IS-IS. The verbose option is required to display flooded TE data.
- show ospf database opaque-area displays the OSPF topology. The opaque-area option is required to display flooded TE data.
- show mpls traffic-eng topology displays the topology as known to TE.
The topology commands can output a huge amount of data for large networks, so make use of the output-reduction and filter options provided.
Link Flooding Issues
If a link isn't flooded into an IGP-area, by TE, there's a several things to check. This section covers them.
Is the link up?
It sounds obvious, but it's good to check this - if only to save embarrassment when someone else points it out to you
Does the IGP have an adjacency over the link?
The first thing to check is that the IGP has an adjacency to at least one neighbor over the link. When the IGP is running more than one area/level, ensure the adjacency is up in the correct area(s).
OSPF
RP/0/0/CPU0:te-ma1#show ospf neighbor
Fri Jul 23 19:37:01.564 UTC
* Indicates MADJ interface
Neighbors for OSPF 0
Neighbor ID Pri State Dead Time Address Interface
102.0.0.2 1 FULL/DR 00:00:36 11.0.0.2 GigabitEthernet0/2/0/0 Neighbor is up for 3d22h
103.0.0.3 1 FULL/DR 00:00:34 11.2.2.3 GigabitEthernet0/2/0/2 Neighbor is up for 3d22h
102.0.0.2 1 FULL/ - 00:00:34 12.0.0.2 POS0/5/0/0 Neighbor is up for 3d22h
103.0.0.3 1 FULL/ - 00:00:35 12.2.2.3 POS0/5/0/2 Neighbor is up for 3d22h
Total neighbor count: 4
Check that:
- The adjacency exists for the interface you're interested in
- The adjacency is up (usually FULL, but see below)
- The adjacency is of the correct type
- P2P adjacencies will have a dash after the adjacency state
- Broadcast adjacencies will have the neighbor's DR role, which will be DR, BDR or DROTHER
- The neighbor's ID and address are correct
- The adjacency is in the correct area (use the detail option on the command for this).
An OSPF adjacency won't be announced to TE until it's in FULL state (i.e. database exchange has been completed). However, OSPF calculates the neighbor uptime from when hello packets were first exchanged. This means that if there's communication problems on the link, it's possible to see OSPF neighbors with relatively long 'uptimes' which are still not fully up (e.g. in EXCHANGE or LOADING state). Note also that this does NOT apply to broadcast links with multiple neighbors; in this case the expected final state is that adjacencies to the DR and BDR will come up to FULL state, but adjacencies to other nodes will only come to EXCHANGE state.
IS-IS
RP/0/0/CPU0:te-ma1#show isis neighbors
Fri Jul 23 19:37:07.139 UTC
IS-IS 0 neighbors:
System Id Interface SNPA State Holdtime Type IETF-NSF
te-ma2 Gi0/2/0/1 0090.86a9.18ff Up 9 L1L2 Capable
te-ma2 PO0/5/0/1 *PtoP* Up 27 L1L2 Capable
te-ma1 Gi0/2/0/3 0002.17ef.70ff Up 24 L1L2 Capable
te-ma1 PO0/5/0/3 *PtoP* Up 27 L1L2 Capable
Total neighbor count: 4
Check that:
- The adjacency exists for the interface you're interested in
- The adjacency is up
- The adjacency is in the correct level (Type column)
- The adjacency is the expected type (P2P or broadcast)
- P2P adjacencies will have a SNPA of *PtoP*
- Broadcast (LAN) adjacencies will have a MAC address SNPA
- The neighbor's ID and address are correct (use the detail option to see addresses). Note that IS-IS will, by default, convert system IDs to hostnames.
If adjacencies are down (or otherwise not fully up), consult the documentation for the relevant protocol to troubleshoot further.
Is TE running over the IGP area?
Make sure that TE is configured to run over the IGP-area that doesn't have the links flooded.
RP/0/0/CPU0:te-ma1#show mpls traffic-eng igp-areas Tue Jul 27 18:07:20.526 UTC MPLS-TE IGP Areas Global router-id: 101.0.0.1 Global optical router-id: Not available IS-IS 0 IGP ID: 0001.0011.0111 TE router ID configured: 101.1.1.1 in use: 101.1.1.1 Link connection: up Topology/tunnel connection: up level 1 TE index: 1 IGP config for TE: complete Local links flooded in this IGP level: 4 Flooding beacon sent and received P2P tunnel heads running over this IGP level: 5 1 AA, 0 FA P2MP destinations running over this IGP level: 0 Tunnel loose-hops expanded over this IGP level: 0 OSPF 0 IGP ID: 101.0.0.1 TE router ID configured: 101.0.0.1 in use: 101.0.0.1 Link connection: up Topology/tunnel connection: up area 1 TE index: 0 IGP config for TE: complete Local links flooded in this IGP area: 4 Flooding beacon sent and received P2P tunnel heads running over this IGP area: 5 1 AA, 0 FA P2MP destinations running over this IGP area: 0 Tunnel loose-hops expanded over this IGP area: 0
Ensure that:
- the IGP instance you expect is present
- If it isn't, ensure the required TE configuration is present in the IGP submode
- The IGP ID is correct - it should be the OSPF router-id or the IS-IS system-id, which is extracted from the IS-IS NET config
- If not, check the IGP config
- The TE router-id is correct
- Check that the configured ID here matches the "mpls traffic-eng router-id" config in the IGP; it may be 0.0.0.0 if nothing is configured
- If the TE router-id config references a Loopback interface, ensure that the Loopback interface exists and has an IP address. If not, the global router-id will be used as the TE router-id instead, and the configured router-id will be displayed as 0.0.0.0.
- If you're deliberately using the global router-id (i.e. you haven't configured "mpls traffic-eng router-id" under the IGP) ensure that the router-id in use is what you expect it to be. Be aware that the XR global router-id may change due to events such as a router reload, IP address configuration changes or interface state changes, so this isn't recommended.
- The area you expect exists within the IGP instance
- The IGP config for the area is OK (the "IGP config for TE: complete" line)
- If not, ensure that the area has TE enabled in the IGP config. For IS-IS, make sure wide metrics are enabled.
- The link and topology connections are up
- it will stay down until there's at least one correctly-configured area within the IGP-instance
- The flooding beacon is "sent and received". This refers to communications between TE and the IGP and if it's in any other state, may indicate a communicatin problem.
If you're sure that the IGP config is correct, and there's problems in this area, then contact Cisco support. Both TE showtech and the relevant IGP showtech output will be required.
Does TE know about the IGP-adjacencies on the link?
show mpls traffic-eng link-management igp-neighbors is a useful command to ensure that TE knows about the IGP adjacencies on each link.
RP/0/0/CPU0:te-ma1#show mpls traffic-eng link-management igp-neighbors Tue Jul 27 18:41:39.372 UTC Link ID:: GigabitEthernet0/2/0/0 Neighbor ID: 11.0.0.2 (OSPF 0 area 1, link address: 0.0.0.0) Link ID:: GigabitEthernet0/2/0/1 Neighbor ID: 0002.0002.0022.00 (IS-IS 0 level 1, link address: 11.1.1.2) Link ID:: POS0/5/0/2 Neighbor ID: 103.0.0.3 (OSPF 0 area 1, link address: 12.2.2.3) Link ID:: POS0/5/0/3 Neighbor ID: 0003.0003.0003.00 (IS-IS 0 level 1, link address: 12.3.3.3)
Note that in the case of a broadcast adjacency, the neighbor address displayed in TE will be the interface address of the DR (for OSPF) or DIS (for IS-IS), which will be the local interface address if the local router is the DR/DIS.
If the adjacency you expect on a link isn't present, make sure that:
- the IGP has an adjacency;
- TE is running over the IGP-area that the adjacency is in;
- TE is configured to run over the link.
If you're running TE over IS-IS, you can also check the log of adjacency updates that IS-IS has sent to TE:
RP/0/0/CPU0:te-ma3#sh isis mpls traffic-eng adjacency-log Wed Jul 28 20:42:06.789 UTC IS-IS 0 Level-1 MPLS Traffic Engineering adjacency log When Neighbor ID IP Address Interface Status --- Mon Jul 19 2010 --- 21:52:58.194 te-ma1 12.3.3.1 PO0/5/0/3 Up 21:53:06.755 te-ma2 11.5.5.2 Gi0/2/0/1 Up 21:53:12.942 te-ma1 11.3.3.1 Gi0/2/0/3 Up 21:53:35.523 te-ma2 12.5.5.2 PO0/5/0/1 Up --- Tue Jul 27 2010 --- 19:07:27.618 te-ma1 0.0.0.0 Gi0/2/0/3 Down 19:07:51.518 te-ma2 0.0.0.0 Gi0/2/0/1 Down 19:07:54.593 te-ma2 11.5.5.2 Gi0/2/0/1 Up 19:07:54.596 te-ma3 11.3.3.3 Gi0/2/0/3 Up
If the adjacency is present but doesn't seem to have made it to TE, make sure both TE and IGP showtechs are provided with any support request.
Does TE have the interface state correct?
RP/0/0/CPU0:te-ma3#show mpls traffic-eng link-management interfaces
Wed Jul 28 18:13:10.770 UTC
System Information::
Links Count : 8 (Maximum Links Supported 250)
Link ID:: GigabitEthernet0/2/0/0 (11.4.4.3)
Local Intf ID: 25
Link Status:
Link Label Type : PSC
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec (reserved: 0% in, 0% out)
BC0 (Res. Global BW): 200000 kbits/sec (reserved: 0% in, 0% out)
BC1 (Res. Sub BW) : 100000 kbits/sec (reserved: 0% in, 0% out)
MPLS TE Link State : MPLS TE on, RSVP on, admin-up
Inbound Admission : reject-huge
Outbound Admission : allow-if-room
IGP Neighbor Count : 1
Max Res BW (RDM) : 200000 kbits/sec
BC0 (RDM) : 200000 kbits/sec
BC1 (RDM) : 100000 kbits/sec
Max Res BW (MAM) : 500000 kbits/sec
BC0 (MAM) : 200000 kbits/sec
BC1 (MAM) : 100000 kbits/sec
Attributes : 0x0
Attribute Names :
Flooding Status: (1 area)
IGP Area[1]: OSPF 0 area 1, flooded
Nbr: ID 11.4.4.3, IP 0.0.0.0 (Up)
Admin weight: not set (TE), 1 (IGP)
Link ID:: GigabitEthernet0/2/0/1 (11.5.5.3)
Local Intf ID: 26
Link Status:
Link Label Type : PSC
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec (reserved: 0% in, 0% out)
BC0 (Res. Global BW): 200000 kbits/sec (reserved: 0% in, 0% out)
BC1 (Res. Sub BW) : 100000 kbits/sec (reserved: 0% in, 0% out)
MPLS TE Link State : MPLS TE on, RSVP on, admin-up
Inbound Admission : reject-huge
Outbound Admission : allow-if-room
IGP Neighbor Count : 1
Max Res BW (RDM) : 200000 kbits/sec
BC0 (RDM) : 200000 kbits/sec
BC1 (RDM) : 100000 kbits/sec
Max Res BW (MAM) : 500000 kbits/sec
BC0 (MAM) : 200000 kbits/sec
BC1 (MAM) : 100000 kbits/sec
Attributes : 0x0
Attribute Names :
Flooding Status: (1 area)
IGP Area[1]: IS-IS 0 level 1, flooded
Nbr: ID 0002.0002.0022.01, IP 11.5.5.2 (Up)
Admin weight: not set (TE), 10 (IGP)
Link ID:: POS0/5/0/0 (12.4.4.3)
Local Intf ID: 14
Link Status:
Link Label Type : PSC
Physical BW : 155520 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec (reserved: 0% in, 0% out)
BC0 (Res. Global BW): 200000 kbits/sec (reserved: 0% in, 0% out)
BC1 (Res. Sub BW) : 100000 kbits/sec (reserved: 0% in, 0% out)
MPLS TE Link State : MPLS TE on, RSVP on, admin-up
Inbound Admission : allow-all
Outbound Admission : allow-if-room
IGP Neighbor Count : 1
Max Res BW (RDM) : 200000 kbits/sec
BC0 (RDM) : 200000 kbits/sec
BC1 (RDM) : 100000 kbits/sec
Max Res BW (MAM) : 500000 kbits/sec
BC0 (MAM) : 200000 kbits/sec
BC1 (MAM) : 100000 kbits/sec
Attributes : 0x0
Attribute Names :
Flooding Status: (1 area)
IGP Area[1]: OSPF 0 area 1, flooded
Nbr: ID 102.0.0.2, IP 12.4.4.2 (Up)
Admin weight: not set (TE), 1 (IGP)
Link ID:: POS0/5/0/1 (12.5.5.3)
Local Intf ID: 17
Link Status:
Link Label Type : PSC
Physical BW : 155520 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec (reserved: 0% in, 0% out)
BC0 (Res. Global BW): 200000 kbits/sec (reserved: 0% in, 0% out)
BC1 (Res. Sub BW) : 100000 kbits/sec (reserved: 0% in, 0% out)
MPLS TE Link State : MPLS TE on, RSVP on, admin-up
Inbound Admission : allow-all
Outbound Admission : allow-if-room
IGP Neighbor Count : 1
Max Res BW (RDM) : 200000 kbits/sec
BC0 (RDM) : 200000 kbits/sec
BC1 (RDM) : 100000 kbits/sec
Max Res BW (MAM) : 500000 kbits/sec
BC0 (MAM) : 200000 kbits/sec
BC1 (MAM) : 100000 kbits/sec
Attributes : 0x0
Attribute Names :
Flooding Status: (1 area)
IGP Area[1]: IS-IS 0 level 1, flooded
Nbr: ID 0002.0002.0022.00, IP 12.5.5.2 (Up)
Admin weight: not set (TE), 10 (IGP)
Make sure that:
- The basic interface details are correct (name, IP address)
- Link state is correct (it should be MPLS TE on, RSVP on, admin-up)
- The bandwidths on the interface are as expected
- The link attributes are OK, if any are configured
- SRLGs are correct, if configured
- Flooding status is correct:
- Link is flooded to correct area(s)
- Neighbor id and address are correct (remember, it's the DR's link address for broadcast links, which may be the local address)
- Admin weights are correct
No IGP adjacency
If there's no IGP adjacencies at all, the flooding status will look like this:
Flooding Status: (0 area) Not flooded: Link has no IGP adjacencies for any area
If the IGP shows an adjacency in an area where TE is correctly configured but TE doesn't know about it, this is a problem. TE and IGP showtechs will be required for any support request.
Link Down
If the link is down:
Flooding Status: (0 area) Not flooded: Interface has been administratively disabled
If the link is up but TE doesn't know the correct state, a support request will require TE and PFI showtechs.
No link IP address
If the link has no IP address, note that 0.0.0.0 is displayed for the link's address. The show command also gives the reason the link isn't flooded:
RP/0/0/CPU0:te-ma1#show mpls traffic-eng link-management interfaces GigabitEthernet0/2/0/0 Wed Jul 28 18:03:36.159 UTC System Information:: Links Count : 8 (Maximum Links Supported 250) Link ID:: GigabitEthernet0/2/0/0 (0.0.0.0) Local Intf ID: 26 Link Status: Link Label Type : PSC Physical BW : 1000000 kbits/sec BCID : RDM Max Reservable BW : 200000 kbits/sec (reserved: 0% in, 0% out) BC0 (Res. Global BW): 200000 kbits/sec (reserved: 0% in, 0% out) BC1 (Res. Sub BW) : 100000 kbits/sec (reserved: 0% in, 0% out) MPLS TE Link State : MPLS TE on, RSVP on, admin-down Inbound Admission : reject-huge Outbound Admission : allow-if-room IGP Neighbor Count : 0 Max Res BW (RDM) : 200000 kbits/sec BC0 (RDM) : 200000 kbits/sec BC1 (RDM) : 100000 kbits/sec Max Res BW (MAM) : 500000 kbits/sec BC0 (MAM) : 200000 kbits/sec BC1 (MAM) : 100000 kbits/sec Attributes : 0x0 Attribute Names : Flooding Status: (0 area) Not flooded: The interface does not have an IP address
An IPv4 address is required; IPv6-only and unnumbered interfaces can't be used by TE in XR.
If the link has an IP address configured that TE doesn't seem to know about, contact Cisco support. Both PFI and TE showtechs will be required.
Forward-referenced links
Forward-referenced interfaces are interfaces that are configured in TE (under the mpls traffic-eng submode), but the interface doesn't exist on the router. This could be because the expected linecard has been removed or is down, or could be because of a mis-configuration in TE. In this case, there will simply be no information for the link:
Link ID:: POS0/4/0/0 (0.0.0.0)
Local Intf ID: 40
Link Status:
Link Label Type : PSC
Physical BW : 0 kbits/sec BCID : RDM
Max Reservable BW : 34359738 kbits/sec (reserved: 0% in, 0% out)
BC0 (Res. Global BW): 34359738 kbits/sec (reserved: 0% in, 0% out)
BC1 (Res. Sub BW) : 34359738 kbits/sec (reserved: 0% in, 0% out)
MPLS TE Link State : admin-up
Inbound Admission : allow-all
Outbound Admission : allow-if-room
IGP Neighbor Count : 0
Max Res BW (RDM) : 0 kbits/sec
BC0 (RDM) : 0 kbits/sec
BC1 (RDM) : 0 kbits/sec
Max Res BW (MAM) : 0 kbits/sec
BC0 (MAM) : 0 kbits/sec
BC1 (MAM) : 0 kbits/sec
Attributes : 0x0
Attribute Names :
Flooding Status: (0 area)
Not flooded:
In particular, not that there's no IP address and no physical bandwidth for the link.
In this case, make sure the link really exists (show interface or show ipv4 interface). If you contact Cisco support, TE and PFI showtechs will be required.
Link missing in TE output entirely
If a link on which TE is configured doesn't exist in the output of show mpls traffic-eng link-management interface at all, TE and PFI showtechs will be required with any support request.
.
SRLG data is wrong
If TE has incorrect SRLG data for a link:
- Make sure the SRLG config for the interface is correct
- Check the output of show srlg to ensure that the system has the correct SRLGs in its master record.
- Ensure that the system has the correct SRLGs on the RP where TE is running with show srlg location <location>.
If assistance is required from Cisco support, both TE and RSI showtechs will be required.
Has TE has flooded the link correctly?
The flooding status discussed in the previous section gives a quick indication of whether the link is flooded or not. However, it may be necessary to inspect the data that has been flooded to the IGP by TE.
RP/0/0/CPU0:te-ma3#show mpls traffic-eng link-management advertisements
Wed Jul 28 18:50:44.532 UTC
Flooding Status : ready
Last Flooding : 84646 seconds ago
Last Flooding Trigger : TE Link came Up
Next Periodic Flooding In : 138 seconds
Diff-Serv TE Mode : Prestandard
Configured Areas : 2
IGP Area[1]:: IS-IS 0 level 1
Flooding Protocol : IS-IS
IGP System ID : 0003.0003.0003
MPLS TE Router ID : 103.1.1.3
Flooded Links : 2
Link ID:: 0 (GigabitEthernet0/2/0/1)
Link IP Address : 11.5.5.3
O/G Intf ID : 26
Designated Router : 0002.0002.0022.01, IP 11.5.5.2
TE Metric : 10
IGP Metric : 10
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
Link ID:: 1 (POS0/5/0/1)
Link IP Address : 12.5.5.3
O/G Intf ID : 17
Neighbor : ID 0002.0002.0022.00, IP 12.5.5.2
TE Metric : 10
IGP Metric : 10
Physical BW : 155520 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
IGP Area[2]:: OSPF 0 area 1
Flooding Protocol : OSPF
IGP System ID : 103.0.0.3
MPLS TE Router ID : 103.0.0.3
Flooded Links : 2
Link ID:: 0 (GigabitEthernet0/2/0/0)
Link IP Address : 11.4.4.3
O/G Intf ID : 25
Designated Router : 11.4.4.3
TE Metric : 1
IGP Metric : 1
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
Link ID:: 1 (POS0/5/0/0)
Link IP Address : 12.4.4.3
O/G Intf ID : 14
Neighbor : ID 102.0.0.2, IP 12.4.4.2
TE Metric : 1
IGP Metric : 1
Physical BW : 155520 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
Check that:
- There's a flooded local LSA for each area TE is running over
- System-id (IS-IS system id, or OSPF's own router-id) and TE router-id information is correct for each area
- The correct links are flooded to each area
- Link addresses are correct
- Neighbor information is correct
- For P2P links, this will be the neighbor's system-id and interface IP address
- For broadcast links, this will be the DR's interface address - which may be the local address if this command is run on the DR.
- Link data (bandwidths, attributes, etc) is correct (bear in mind thresholds and rounding issues when checking link bandwidths; these are discussed later in this document)
Has the IGP has received the flooded link from TE?
The local-LSA flooded by TE to the IGP is flooded to the network by the IGP on TE's behalf. In order to make sure that the IGP has received the correct local-LSA information, check the IGP's own record of what has been flooded.
IS-IS:
IS-IS 0 Level-1 MPLS Traffic Engineering advertisements
System ID: te-ma3
Router ID: 103.1.1.3
Link Count: 2
Link[0]
Neighbor System ID: te-ma2 (broadcast link)
Interface IP address: 11.5.5.3
Neighbor IP Address: 11.5.5.2
TE Metric: 10
Physical BW: 1000000 kbits/sec
Reservable BW global: 200000 kbits/sec
Reservable BW sub: 100000 kbits/sec
Global pool BW unreserved:
[0]: 200000 kbits/sec, [1]: 200000 kbits/sec
[2]: 200000 kbits/sec, [3]: 200000 kbits/sec
[4]: 200000 kbits/sec, [5]: 200000 kbits/sec
[6]: 200000 kbits/sec, [7]: 200000 kbits/sec
Sub pool BW unreserved:
[0]: 100000 kbits/sec, [1]: 100000 kbits/sec
[2]: 100000 kbits/sec, [3]: 100000 kbits/sec
[4]: 100000 kbits/sec, [5]: 100000 kbits/sec
[6]: 100000 kbits/sec, [7]: 100000 kbits/sec
Affinity Bits: 0x00000000
Link[1]
Neighbor System ID: te-ma2 (P2P link)
Interface IP address: 12.5.5.3
Neighbor IP Address: 12.5.5.2
TE Metric: 10
Physical BW: 155520 kbits/sec
Reservable BW global: 200000 kbits/sec
Reservable BW sub: 100000 kbits/sec
Global pool BW unreserved:
[0]: 200000 kbits/sec, [1]: 200000 kbits/sec
[2]: 200000 kbits/sec, [3]: 200000 kbits/sec
[4]: 200000 kbits/sec, [5]: 200000 kbits/sec
[6]: 200000 kbits/sec, [7]: 200000 kbits/sec
Sub pool BW unreserved:
[0]: 100000 kbits/sec, [1]: 100000 kbits/sec
[2]: 100000 kbits/sec, [3]: 100000 kbits/sec
[4]: 100000 kbits/sec, [5]: 100000 kbits/sec
[6]: 100000 kbits/sec, [7]: 100000 kbits/sec
Affinity Bits: 0x00000000
OSPF:
RP/0/0/CPU0:te-ma3#show ospf mpls traffic-eng link
Wed Jul 28 20:47:19.431 UTC
OSPF Router with ID (103.0.0.3) (Process ID 0)
Area 1 has 2 MPLS TE links. Area instance is 20.
Link is associated with fragment 3. Link instance is 20
Link connected to Point-to-Point network
Link ID : 102.0.0.2
Interface Address : 12.4.4.3
Neighbor Address : 12.4.4.2
Admin Metric : TE: 1
(all bandwidths in bytes/sec)
Maximum bandwidth : 19440000
Maximum global pool reservable bandwidth : 25000000
Maximum sub pool reservable bandwidth : 12500000
Number of Priority : 8
Global pool unreserved BW
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Sub pool unreserved BW
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
Out Interface ID : 14
Affinity Bit : 0
Link is associated with fragment 1. Link instance is 20
Link connected to Broadcast network
Link ID : 11.4.4.3
Interface Address : 11.4.4.3
Admin Metric : TE: 1
(all bandwidths in bytes/sec)
Maximum bandwidth : 125000000
Maximum global pool reservable bandwidth : 25000000
Maximum sub pool reservable bandwidth : 12500000
Number of Priority : 8
Global pool unreserved BW
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Sub pool unreserved BW
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
Out Interface ID : 25
Affinity Bit : 0
Ensure that the link data given by these commands corresponds to what TE flooded (show mpls traffic-eng link-management advertisements). Any support request for issues in this area will require both TE and IGP showtechs.
Topology problems
Once TE has flooded its local LSA information to the IGP, the IGP will flood this throughout the network.
Does the IGP have the topology complete?
Since the IGP is responsible for flooding, we need to ensure that the network topology is complete. There are some differences between the way IS-IS and OSPF flood TE information:
- OSPF floods the basic router-information (router-id, etc) in LSA fragment 0
- OSPF then floods one link per fragment.
The link's fragment id is, in fact, the corresponding interface's SNMP interface index (this is an XR-specific detail; other implementations may well do things differently). - IS-IS floods as much information as possible in each LSA fragment; it will only fragment LSAs when there's enough data (or the network MTU is low enough) that fragmentation is required.
When validating the topology in the IGP, check that:
- The TE router-id is flooded correctly
- Each link is flooded correctly, with the correct
- local IP address
- neighbor address
- link attributes
- bandwidth information
- Any required pseudonodes are present for broadcast links
These checks need to be done in each IGP-area running TE. It is also necessary to check that the data for each router is correct, on each router. Yes, that's a lot of checking! No matter which IGP you're using, it's very important that the topology is the same on all routers.
If topology changes made on one router aren't getting flooded throughout the network (i.e. if discrepancies exist), this probably indicates a general IGP flooding problem.
If information for a particular link or router is wrong or missing, but is consistent throughout the network, then there's probably a flooding problem on the originating router; consult the flooding section of this page to debug further on that router.
IS-IS
RP/0/0/CPU0:te-ma1#show isis database verbose
Thu Jul 29 21:08:56.884 UTC
IS-IS 0 (Level-1) Link State Database
LSPID LSP Seq Num LSP Checksum LSP Holdtime ATT/P/OL
te-ma1.00-00 * 0x00000029 0x0670 1189 0/0/0
Area Address: 49
NLPID: 0xcc
Hostname: te-ma1
IP Address: 101.1.1.1
Router ID: 101.1.1.1
Metric: 10 IS-Extended te-ma2.03
Affinity: 0x00000000
Interface IP Address: 11.1.1.1
Neighbor IP Address: 11.1.1.2
Physical BW: 1000000 kbits/sec
Reservable Global pool BW: 200000 kbits/sec
Global Pool BW Unreserved:
[0]: 200000 kbits/sec [1]: 200000 kbits/sec
[2]: 200000 kbits/sec [3]: 200000 kbits/sec
[4]: 200000 kbits/sec [5]: 200000 kbits/sec
[6]: 200000 kbits/sec [7]: 200000 kbits/sec
Reservable Sub pool BW: 100000 kbits/sec
Sub pool BW Unreserved:
[0]: 100000 kbits/sec [1]: 100000 kbits/sec
[2]: 100000 kbits/sec [3]: 100000 kbits/sec
[4]: 100000 kbits/sec [5]: 100000 kbits/sec
[6]: 100000 kbits/sec [7]: 100000 kbits/sec
Metric: 10 IS-Extended te-ma2.00
Affinity: 0x00000000
Interface IP Address: 12.1.1.1
Neighbor IP Address: 12.1.1.2
Physical BW: 155520 kbits/sec
Reservable Global pool BW: 200000 kbits/sec
Global Pool BW Unreserved:
[0]: 200000 kbits/sec [1]: 200000 kbits/sec
[2]: 200000 kbits/sec [3]: 200000 kbits/sec
[4]: 200000 kbits/sec [5]: 200000 kbits/sec
[6]: 200000 kbits/sec [7]: 200000 kbits/sec
Reservable Sub pool BW: 100000 kbits/sec
Sub pool BW Unreserved:
[0]: 100000 kbits/sec [1]: 100000 kbits/sec
[2]: 100000 kbits/sec [3]: 100000 kbits/sec
[4]: 100000 kbits/sec [5]: 100000 kbits/sec
[6]: 100000 kbits/sec [7]: 100000 kbits/sec
Metric: 10 IP-Extended 11.1.1.0/24
Metric: 10 IP-Extended 12.1.1.0/24
Metric: 0 IP-Extended 101.1.1.1/32
te-ma2.00-00 0x00000025 0xd480 1010 0/0/0
Area Address: 49
NLPID: 0xcc
Hostname: te-ma2
IP Address: 102.1.1.2
Router ID: 102.1.1.2
Metric: 10 IS-Extended te-ma2.01
Affinity: 0x00000000
Interface IP Address: 11.5.5.2
Neighbor IP Address: 11.5.5.2
Physical BW: 1000000 kbits/sec
Reservable Global pool BW: 200000 kbits/sec
Global Pool BW Unreserved:
[0]: 200000 kbits/sec [1]: 200000 kbits/sec
[2]: 200000 kbits/sec [3]: 200000 kbits/sec
[4]: 200000 kbits/sec [5]: 200000 kbits/sec
[6]: 200000 kbits/sec [7]: 200000 kbits/sec
Reservable Sub pool BW: 100000 kbits/sec
Sub pool BW Unreserved:
[0]: 100000 kbits/sec [1]: 100000 kbits/sec
[2]: 100000 kbits/sec [3]: 100000 kbits/sec
[4]: 100000 kbits/sec [5]: 100000 kbits/sec
[6]: 100000 kbits/sec [7]: 100000 kbits/sec
Metric: 10 IS-Extended te-ma2.03
Affinity: 0x00000000
Interface IP Address: 11.1.1.2
Neighbor IP Address: 11.1.1.2
Physical BW: 1000000 kbits/sec
Reservable Global pool BW: 200000 kbits/sec
Global Pool BW Unreserved:
[0]: 200000 kbits/sec [1]: 200000 kbits/sec
[2]: 200000 kbits/sec [3]: 200000 kbits/sec
[4]: 200000 kbits/sec [5]: 200000 kbits/sec
[6]: 200000 kbits/sec [7]: 200000 kbits/sec
Reservable Sub pool BW: 100000 kbits/sec
Sub pool BW Unreserved:
[0]: 100000 kbits/sec [1]: 100000 kbits/sec
[2]: 100000 kbits/sec [3]: 100000 kbits/sec
[4]: 100000 kbits/sec [5]: 100000 kbits/sec
[6]: 100000 kbits/sec [7]: 100000 kbits/sec
Metric: 10 IS-Extended te-ma3.00
Affinity: 0x00000000
Interface IP Address: 12.5.5.2
Neighbor IP Address: 12.5.5.3
Physical BW: 155520 kbits/sec
Reservable Global pool BW: 200000 kbits/sec
Global Pool BW Unreserved:
[0]: 200000 kbits/sec [1]: 200000 kbits/sec
[2]: 200000 kbits/sec [3]: 200000 kbits/sec
[4]: 200000 kbits/sec [5]: 200000 kbits/sec
[6]: 200000 kbits/sec [7]: 200000 kbits/sec
Reservable Sub pool BW: 100000 kbits/sec
Sub pool BW Unreserved:
[0]: 100000 kbits/sec [1]: 100000 kbits/sec
[2]: 100000 kbits/sec [3]: 100000 kbits/sec
[4]: 100000 kbits/sec [5]: 100000 kbits/sec
[6]: 100000 kbits/sec [7]: 100000 kbits/sec
Metric: 10 IS-Extended te-ma1.00
Affinity: 0x00000000
Interface IP Address: 12.1.1.2
Neighbor IP Address: 12.1.1.1
Physical BW: 155520 kbits/sec
Reservable Global pool BW: 200000 kbits/sec
Global Pool BW Unreserved:
[0]: 200000 kbits/sec [1]: 200000 kbits/sec
[2]: 200000 kbits/sec [3]: 200000 kbits/sec
[4]: 200000 kbits/sec [5]: 200000 kbits/sec
[6]: 200000 kbits/sec [7]: 200000 kbits/sec
Reservable Sub pool BW: 100000 kbits/sec
Sub pool BW Unreserved:
[0]: 100000 kbits/sec [1]: 100000 kbits/sec
[2]: 100000 kbits/sec [3]: 100000 kbits/sec
[4]: 100000 kbits/sec [5]: 100000 kbits/sec
[6]: 100000 kbits/sec [7]: 100000 kbits/sec
Metric: 10 IP-Extended 11.1.1.0/24
Metric: 10 IP-Extended 11.5.5.0/24
Metric: 10 IP-Extended 12.1.1.0/24
Metric: 10 IP-Extended 12.5.5.0/24
Metric: 0 IP-Extended 102.1.1.2/32
te-ma2.01-00 0x00000019 0xe878 1164 0/0/0
Metric: 0 IS-Extended te-ma2.00
Metric: 0 IS-Extended te-ma3.00
te-ma2.03-00 0x00000004 0x0e4b 1028 0/0/0
Metric: 0 IS-Extended te-ma2.00
Metric: 0 IS-Extended te-ma1.00
te-ma3.00-00 0x00000025 0xfb59 1187 0/0/0
Area Address: 49
NLPID: 0xcc
Hostname: te-ma3
IP Address: 103.1.1.3
Router ID: 103.1.1.3
Metric: 10 IS-Extended te-ma2.01
Affinity: 0x00000000
Interface IP Address: 11.5.5.3
Neighbor IP Address: 11.5.5.2
Physical BW: 1000000 kbits/sec
Reservable Global pool BW: 200000 kbits/sec
Global Pool BW Unreserved:
[0]: 200000 kbits/sec [1]: 200000 kbits/sec
[2]: 200000 kbits/sec [3]: 200000 kbits/sec
[4]: 200000 kbits/sec [5]: 200000 kbits/sec
[6]: 200000 kbits/sec [7]: 200000 kbits/sec
Reservable Sub pool BW: 100000 kbits/sec
Sub pool BW Unreserved:
[0]: 100000 kbits/sec [1]: 100000 kbits/sec
[2]: 100000 kbits/sec [3]: 100000 kbits/sec
[4]: 100000 kbits/sec [5]: 100000 kbits/sec
[6]: 100000 kbits/sec [7]: 100000 kbits/sec
Metric: 10 IS-Extended te-ma2.00
Affinity: 0x00000000
Interface IP Address: 12.5.5.3
Neighbor IP Address: 12.5.5.2
Physical BW: 155520 kbits/sec
Reservable Global pool BW: 200000 kbits/sec
Global Pool BW Unreserved:
[0]: 200000 kbits/sec [1]: 200000 kbits/sec
[2]: 200000 kbits/sec [3]: 200000 kbits/sec
[4]: 200000 kbits/sec [5]: 200000 kbits/sec
[6]: 200000 kbits/sec [7]: 200000 kbits/sec
Reservable Sub pool BW: 100000 kbits/sec
Sub pool BW Unreserved:
[0]: 100000 kbits/sec [1]: 100000 kbits/sec
[2]: 100000 kbits/sec [3]: 100000 kbits/sec
[4]: 100000 kbits/sec [5]: 100000 kbits/sec
[6]: 100000 kbits/sec [7]: 100000 kbits/sec
Metric: 10 IP-Extended 11.5.5.0/24
Metric: 10 IP-Extended 12.5.5.0/24
Metric: 0 IP-Extended 103.1.1.3/32
te-ma3.01-00 0x00000019 0x0000 0 (1190) 0/0/0
Total Level-1 LSP count: 6 Local Level-1 LSP count: 1
The verbose option is necessary here to have the TE data displayed in the command output.
Note that the pseudonode LSAs for LAN circuits are also visible in the database, as well as the router node data generated by TE. The pseudonode LSAs are generated by IS-IS without any involvement from TE - if they aren't present when they should be, this is probably an IS-IS issue rather than a TE one.
OSPF
RP/0/0/CPU0:te-ma1#show ospf database opaque-area
Fri Jul 30 19:32:36.698 UTC
OSPF Router with ID (101.0.0.1) (Process ID 0)
Type-10 Opaque Link Area Link States (Area 1)
LS age: 1895
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.0
Opaque Type: 1
Opaque ID: 0
Advertising Router: 101.0.0.1
LS Seq Number: 8000002f
Checksum: 0x3106
Length: 28
MPLS TE router ID : 101.0.0.1
Number of Links : 0
LS age: 308
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.0
Opaque Type: 1
Opaque ID: 0
Advertising Router: 102.0.0.2
LS Seq Number: 80000030
Checksum: 0x3101
Length: 28
MPLS TE router ID : 102.0.0.2
Number of Links : 0
LS age: 655
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.0
Opaque Type: 1
Opaque ID: 0
Advertising Router: 103.0.0.3
LS Seq Number: 80000030
Checksum: 0x33fa
Length: 28
MPLS TE router ID : 103.0.0.3
Number of Links : 0
LS age: 308
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.14
Opaque Type: 1
Opaque ID: 14
Advertising Router: 102.0.0.2
LS Seq Number: 80000031
Checksum: 0xca52
Length: 176
Link connected to Point-to-Point network
Link ID : 101.0.0.1
(all bandwidths in bytes/sec)
Interface Address : 12.0.0.2
Neighbor Address : 12.0.0.1
Admin Metric : 1
Maximum bandwidth : 19440000
Maximum reservable bandwidth global: 25000000
Number of Priority : 8
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Affinity Bit : 0
Maximum reservable sub-pool bandwidth : 12500000
Number of Priority : 8
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
IGP Metric : 1
Number of Links : 1
LS age: 655
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.14
Opaque Type: 1
Opaque ID: 14
Advertising Router: 103.0.0.3
LS Seq Number: 80000031
Checksum: 0x33d3
Length: 176
Link connected to Point-to-Point network
Link ID : 102.0.0.2
(all bandwidths in bytes/sec)
Interface Address : 12.4.4.3
Neighbor Address : 12.4.4.2
Admin Metric : 1
Maximum bandwidth : 19440000
Maximum reservable bandwidth global: 25000000
Number of Priority : 8
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Affinity Bit : 0
Maximum reservable sub-pool bandwidth : 12500000
Number of Priority : 8
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
IGP Metric : 1
Number of Links : 1
LS age: 888
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.15
Opaque Type: 1
Opaque ID: 15
Advertising Router: 101.0.0.1
LS Seq Number: 8000002a
Checksum: 0xf14
Length: 176
Link connected to Point-to-Point network
Link ID : 102.0.0.2
(all bandwidths in bytes/sec)
Interface Address : 12.0.0.1
Neighbor Address : 12.0.0.2
Admin Metric : 1
Maximum bandwidth : 19440000
Maximum reservable bandwidth global: 25000000
Number of Priority : 8
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Affinity Bit : 0
Maximum reservable sub-pool bandwidth : 12500000
Number of Priority : 8
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
IGP Metric : 1
Number of Links : 1
LS age: 1308
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.20
Opaque Type: 1
Opaque ID: 20
Advertising Router: 102.0.0.2
LS Seq Number: 80000037
Checksum: 0x2bcf
Length: 176
Link connected to Point-to-Point network
Link ID : 103.0.0.3
(all bandwidths in bytes/sec)
Interface Address : 12.4.4.2
Neighbor Address : 12.4.4.3
Admin Metric : 1
Maximum bandwidth : 19440000
Maximum reservable bandwidth global: 25000000
Number of Priority : 8
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Affinity Bit : 0
Maximum reservable sub-pool bandwidth : 12500000
Number of Priority : 8
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
IGP Metric : 1
Number of Links : 1
LS age: 308
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.25
Opaque Type: 1
Opaque ID: 25
Advertising Router: 102.0.0.2
LS Seq Number: 80000031
Checksum: 0x4e64
Length: 168
Link connected to Broadcast network
Link ID : 11.0.0.2
(all bandwidths in bytes/sec)
Interface Address : 11.0.0.2
Admin Metric : 1
Maximum bandwidth : 125000000
Maximum reservable bandwidth global: 25000000
Number of Priority : 8
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Affinity Bit : 0
Maximum reservable sub-pool bandwidth : 12500000
Number of Priority : 8
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
IGP Metric : 1
Number of Links : 1
LS age: 655
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.25
Opaque Type: 1
Opaque ID: 25
Advertising Router: 103.0.0.3
LS Seq Number: 80000031
Checksum: 0xfca1
Length: 168
Link connected to Broadcast network
Link ID : 11.4.4.3
(all bandwidths in bytes/sec)
Interface Address : 11.4.4.3
Admin Metric : 1
Maximum bandwidth : 125000000
Maximum reservable bandwidth global: 25000000
Number of Priority : 8
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Affinity Bit : 0
Maximum reservable sub-pool bandwidth : 12500000
Number of Priority : 8
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
IGP Metric : 1
Number of Links : 1
LS age: 888
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.26
Opaque Type: 1
Opaque ID: 26
Advertising Router: 101.0.0.1
LS Seq Number: 8000002a
Checksum: 0x4378
Length: 168
Link connected to Broadcast network
Link ID : 11.0.0.2
(all bandwidths in bytes/sec)
Interface Address : 11.0.0.1
Admin Metric : 1
Maximum bandwidth : 125000000
Maximum reservable bandwidth global: 25000000
Number of Priority : 8
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Affinity Bit : 0
Maximum reservable sub-pool bandwidth : 12500000
Number of Priority : 8
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
IGP Metric : 1
Number of Links : 1
LS age: 1308
Options: (No TOS-capability, DC)
LS Type: Opaque Area Link
Link State ID: 1.0.0.27
Opaque Type: 1
Opaque ID: 27
Advertising Router: 102.0.0.2
LS Seq Number: 80000034
Checksum: 0xd3c8
Length: 168
Link connected to Broadcast network
Link ID : 11.4.4.3
(all bandwidths in bytes/sec)
Interface Address : 11.4.4.2
Admin Metric : 1
Maximum bandwidth : 125000000
Maximum reservable bandwidth global: 25000000
Number of Priority : 8
Priority 0 : 25000000 Priority 1 : 25000000
Priority 2 : 25000000 Priority 3 : 25000000
Priority 4 : 25000000 Priority 5 : 25000000
Priority 6 : 25000000 Priority 7 : 25000000
Affinity Bit : 0
Maximum reservable sub-pool bandwidth : 12500000
Number of Priority : 8
Priority 0 : 12500000 Priority 1 : 12500000
Priority 2 : 12500000 Priority 3 : 12500000
Priority 4 : 12500000 Priority 5 : 12500000
Priority 6 : 12500000 Priority 7 : 12500000
IGP Metric : 1
Number of Links : 1
The pseudonodes for OSPF aren't visible with this show command as they're a different LSA type; use show ospf database network to see them. Again, they're generated by OSPF itself, rather than TE - if they aren't present when they should be, this probably indicates an OSPF issue.
RP/0/0/CPU0:te-ma1#show ospf database network Fri Jul 30 19:52:10.496 UTC OSPF Router with ID (101.0.0.1) (Process ID 0) Net Link States (Area 1) Routing Bit Set on this LSA LS age: 202 Options: (No TOS-capability, DC) LS Type: Network Links Link State ID: 11.0.0.2 (address of Designated Router) Advertising Router: 102.0.0.2 LS Seq Number: 80000033 Checksum: 0x447f Length: 32 Network Mask: /24 Attached Router: 101.0.0.1 Attached Router: 102.0.0.2 Routing Bit Set on this LSA LS age: 324 Options: (No TOS-capability, DC) LS Type: Network Links Link State ID: 11.4.4.3 (address of Designated Router) Advertising Router: 103.0.0.3 LS Seq Number: 80000033 Checksum: 0xf8bb Length: 32 Network Mask: /24 Attached Router: 102.0.0.2 Attached Router: 103.0.0.3
Does the TE have the topology complete?
show mpls traffic-eng topology produces a lot of output. It's therefore a good idea to use options on it to reduce this where possible, and worth getting to know what the various options do so that you can use whichever one's most appropriate for the information you're trying to find. Note that the examples given in this section cover both the IS-IS and OSPF topologies used as examples in the previous section.
A first look
show mpls traffic-eng topology model-type rdm (or model-type dste, if you've configured DS-TE in the network) and show mpls traffic-eng topology summary give the briefest available summaries of the topology. Both are useful for quick sanity checks.
The model-type version of the command gives a simple list of nodes and links. Network pseudonodes are not displayed.
RP/0/0/CPU0:te-ma1#show mpls traffic-eng topology model-type rdm
Fri Jul 30 20:07:50.893 UTC
IGP Id: 0001.0011.0111.00, MPLS TE Id: 101.1.1.1 Router Node (IS-IS 0 level-1)
Link[0]: Intf Address: 11.1.1.1, DR: 0002.0002.0022.03
Link[1]: Intf Address: 12.1.1.1, Nbr Intf Address: 12.1.1.2
IGP Id: 0002.0002.0022.00, MPLS TE Id: 102.1.1.2 Router Node (IS-IS 0 level-1)
Link[0]: Intf Address: 11.5.5.2, DR: 0002.0002.0022.01
Link[1]: Intf Address: 11.1.1.2, DR: 0002.0002.0022.03
Link[2]: Intf Address: 12.5.5.2, Nbr Intf Address: 12.5.5.3
Link[3]: Intf Address: 12.1.1.2, Nbr Intf Address: 12.1.1.1
IGP Id: 0003.0003.0003.00, MPLS TE Id: 103.1.1.3 Router Node (IS-IS 0 level-1)
Link[0]: Intf Address: 11.5.5.3, DR: 0002.0002.0022.01
Link[1]: Intf Address: 12.5.5.3, Nbr Intf Address: 12.5.5.2
IGP Id: 101.0.0.1, MPLS TE Id: 101.0.0.1 Router Node (OSPF 0 area 1)
Link[0]: Intf Address: 11.0.0.1, DR: 11.0.0.2
Link[1]: Intf Address: 12.0.0.1, Nbr Intf Address: 12.0.0.2
IGP Id: 102.0.0.2, MPLS TE Id: 102.0.0.2 Router Node (OSPF 0 area 1)
Link[0]: Intf Address: 12.0.0.2, Nbr Intf Address: 12.0.0.1
Link[1]: Intf Address: 12.4.4.2, Nbr Intf Address: 12.4.4.3
Link[2]: Intf Address: 11.0.0.2, DR: 11.0.0.2
Link[3]: Intf Address: 11.4.4.2, DR: 11.4.4.3
IGP Id: 103.0.0.3, MPLS TE Id: 103.0.0.3 Router Node (OSPF 0 area 1)
Link[0]: Intf Address: 12.4.4.3, Nbr Intf Address: 12.4.4.2
Link[1]: Intf Address: 11.4.4.3, DR: 11.4.4.3
For each node, we have:
- The IGP system ID (OSPF router-id or IS-IS system-id)
- TE router-id
- The IGP-area that the node is in
For each link, we have:
- The link's local address
- Neighbor information
Note the difference in the way that p2p and broadcast links are displayed:
- for p2p links, the neighbor's interface address is given
- for broadcast links:
- for IS-IS, the IS-IS node-id of the network pseudonode is given. The first six bytes of this are the system-id of the generating router (DIS).
- for OSPF, the DR's interface address is given; on the DR this is the same as the interface address.
The summary version of the command doesn't display links, but does display network pseudonodes.
RP/0/0/CPU0:te-ma1#show mpls traffic-eng topology summary
Fri Jul 30 20:09:18.593 UTC
My_System_id: 101.0.0.1 (OSPF 0 area 1)
My_System_id: 0001.0011.0111.00 (IS-IS 0 level-1)
My_BC_Model_Type: RDM
Signalling error holddown: 10 sec Global Link Generation 51394
IS-IS 0 level 1
Local System Id: 0001.0011.0111
TE router ID configured: 101.1.1.1
in use: 101.1.1.1
IGP Id: 0001.0011.0111.00, MPLS TE Id: 101.1.1.1 Router Node
2 links
IGP Id: 0002.0002.0022.00, MPLS TE Id: 102.1.1.2 Router Node
4 links
IGP Id: 0003.0003.0003.00, MPLS TE Id: 103.1.1.3 Router Node
2 links
IGP Id: 0002.0002.0022.01, Network Node
2 links
IGP Id: 0002.0002.0022.03, Network Node
2 links
Total: 5 nodes (3 router, 2 network), 12 links
OSPF 0 area 1
Local System Id: 101.0.0.1
TE router ID configured: 101.0.0.1
in use: 101.0.0.1
IGP Id: 101.0.0.1, MPLS TE Id: 101.0.0.1 Router Node
2 links
IGP Id: 102.0.0.2, MPLS TE Id: 102.0.0.2 Router Node
4 links
IGP Id: 103.0.0.3, MPLS TE Id: 103.0.0.3 Router Node
2 links
IGP Id: 11.0.0.2, Network Node
2 links
IGP Id: 11.4.4.3, Network Node
2 links
Total: 5 nodes (3 router, 2 network), 12 links
Grand Total: 10 nodes (6 router, 4 network) 24 links
RP/0/0/CPU0:te-ma1#
These two commands are very useful to check for:
- router nodes that are missing entirely (both)
- network nodes that are absent (summary command)
- missing links (model-type command)
- missing IP addresses (model-type command)
If data is found to be missing in the TE topology, then check that the IGP topology is complete. If the IGP topology is complete then we probably have a communication issue between TE and the IGP; in this case both TE and IGP showtechs will be required for any support request. If the information is missing in the IGP topology, keep investigating to find out what's gone wrong.
Many issues parts of the topology missing (or the entire topology missing) end up being due to missing config somewhere - so it's worth double-checking this. If the entire topology is missing, also check the output of show mpls traffic-eng igp-areas and ensure that the connections between TE and the IGP are up.
Note that each router is seen as a separate node in each IGP-area. This means that if you're running more than one IGP-area over the same routers and links, the topology can rapidly become extremely large. Consider making use of the various filter options available, if appropriate.
IS-IS Overload bit
If the OL-bit is set on a node in an IS-IS topology, the router node will be shown in the TE topology like this:
IGP Id: 0001.0011.0111.00, MPLS TE Id: 101.1.1.1 Router Node (NO SPF) (IS-IS 0 level-1)
Note the NO SPF designation for the node. TE will exclude a node with the OL bit set from its cSPF calculations unless configured to ignore it.
Links in more detail
The brief option to the TE topology show command displays all nodes and links, but omits most of the bandwidth data.
RP/0/0/CPU0:te-ma1#show mpls traffic-eng topology brief
Tue Aug 3 18:12:11.095 UTC
My_System_id: 101.0.0.1 (OSPF 0 area 1)
My_System_id: 0001.0011.0111.00 (IS-IS 0 level-1)
My_BC_Model_Type: RDM
Signalling error holddown: 10 sec Global Link Generation 194011
IGP Id: 0001.0011.0111.00, MPLS TE Id: 101.1.1.1 Router Node (IS-IS 0 level-1)
Link[0]:Broadcast, DR:0002.0002.0022.03, Nbr Node Id:18, gen:194000
Frag Id:0, Intf Address:11.1.1.1, Intf Id:0
Nbr Intf Address:11.1.1.2, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x48
Attribute Names: blue yellow
SRLGs: 5
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:1000000 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[1]:Point-to-Point, Nbr IGP Id:0002.0002.0022.00, Nbr Node Id:13, gen:194001
Frag Id:0, Intf Address:12.1.1.1, Intf Id:0
Nbr Intf Address:12.1.1.2, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x42
Attribute Names: red yellow
SRLGs: 3, 20
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
IGP Id: 0002.0002.0022.00, MPLS TE Id: 102.1.1.2 Router Node (IS-IS 0 level-1)
Link[0]:Broadcast, DR:0002.0002.0022.01, Nbr Node Id:14, gen:194002
Frag Id:0, Intf Address:11.5.5.2, Intf Id:0
Nbr Intf Address:11.5.5.2, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x48
Attribute Names: blue yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:1000000 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[1]:Broadcast, DR:0002.0002.0022.03, Nbr Node Id:18, gen:194003
Frag Id:0, Intf Address:11.1.1.2, Intf Id:0
Nbr Intf Address:11.1.1.2, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x48
Attribute Names: blue yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:1000000 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[2]:Point-to-Point, Nbr IGP Id:0003.0003.0003.00, Nbr Node Id:15, gen:194004
Frag Id:0, Intf Address:12.5.5.2, Intf Id:0
Nbr Intf Address:12.5.5.3, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x2
Attribute Names: red
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[3]:Point-to-Point, Nbr IGP Id:0001.0011.0111.00, Nbr Node Id:12, gen:194005
Frag Id:0, Intf Address:12.1.1.2, Intf Id:0
Nbr Intf Address:12.1.1.1, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x42
Attribute Names: red yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
IGP Id: 0003.0003.0003.00, MPLS TE Id: 103.1.1.3 Router Node (IS-IS 0 level-1)
Link[0]:Broadcast, DR:0002.0002.0022.01, Nbr Node Id:14, gen:194008
Frag Id:0, Intf Address:11.5.5.3, Intf Id:0
Nbr Intf Address:11.5.5.2, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x48
Attribute Names: blue yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:1000000 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[1]:Point-to-Point, Nbr IGP Id:0002.0002.0022.00, Nbr Node Id:13, gen:194009
Frag Id:0, Intf Address:12.5.5.3, Intf Id:0
Nbr Intf Address:12.5.5.2, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x42
Attribute Names: red yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
IGP Id: 0002.0002.0022.01, Network Node (IS-IS 0 level-1)
Link[0]:Broadcast, DR:0002.0002.0022.00, Nbr Node Id:13, gen:194006
Physical BW:0 (kbps), Max Reservable BW Global:0 (kbps)
Max Reservable BW Sub:0 (kbps)
Link[1]:Broadcast, DR:0003.0003.0003.00, Nbr Node Id:15, gen:194007
Physical BW:0 (kbps), Max Reservable BW Global:0 (kbps)
Max Reservable BW Sub:0 (kbps)
IGP Id: 0002.0002.0022.03, Network Node (IS-IS 0 level-1)
Link[0]:Broadcast, DR:0002.0002.0022.00, Nbr Node Id:13, gen:194010
Physical BW:0 (kbps), Max Reservable BW Global:0 (kbps)
Max Reservable BW Sub:0 (kbps)
Link[1]:Broadcast, DR:0001.0011.0111.00, Nbr Node Id:12, gen:194011
Physical BW:0 (kbps), Max Reservable BW Global:0 (kbps)
Max Reservable BW Sub:0 (kbps)
IGP Id: 101.0.0.1, MPLS TE Id: 101.0.0.1 Router Node (OSPF 0 area 1)
Link[0]:Broadcast, DR:11.0.0.2, Nbr Node Id:1, gen:193992
Frag Id:26, Intf Address:11.0.0.1, Intf Id:0
Nbr Intf Address:0.0.0.0, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x48
Attribute Names: blue yellow
SRLGs: 5
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:1000000 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[1]:Point-to-Point, Nbr IGP Id:102.0.0.2, Nbr Node Id:5, gen:193993
Frag Id:15, Intf Address:12.0.0.1, Intf Id:0
Nbr Intf Address:12.0.0.2, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x42
Attribute Names: red yellow
SRLGs: 20, 30 Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
IGP Id: 102.0.0.2, MPLS TE Id: 102.0.0.2 Router Node (OSPF 0 area 1)
Link[0]:Point-to-Point, Nbr IGP Id:101.0.0.1, Nbr Node Id:4, gen:193994
Frag Id:14, Intf Address:12.0.0.2, Intf Id:0
Nbr Intf Address:12.0.0.1, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x42
Attribute Names: red yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[1]:Point-to-Point, Nbr IGP Id:103.0.0.3, Nbr Node Id:6, gen:193995
Frag Id:20, Intf Address:12.4.4.2, Intf Id:0
Nbr Intf Address:12.4.4.3, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x2
Attribute Names: red
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[2]:Broadcast, DR:11.0.0.2, Nbr Node Id:1, gen:193996
Frag Id:25, Intf Address:11.0.0.2, Intf Id:0
Nbr Intf Address:0.0.0.0, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x48
Attribute Names: blue yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:1000000 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[3]:Broadcast, DR:11.4.4.3, Nbr Node Id:3, gen:193997
Frag Id:27, Intf Address:11.4.4.2, Intf Id:0
Nbr Intf Address:0.0.0.0, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x48
Attribute Names: blue yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:1000000 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
IGP Id: 103.0.0.3, MPLS TE Id: 103.0.0.3 Router Node (OSPF 0 area 1)
Link[0]:Point-to-Point, Nbr IGP Id:102.0.0.2, Nbr Node Id:5, gen:193998
Frag Id:14, Intf Address:12.4.4.3, Intf Id:0
Nbr Intf Address:12.4.4.2, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x42
Attribute Names: red yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Link[1]:Broadcast, DR:11.4.4.3, Nbr Node Id:3, gen:193999
Frag Id:25, Intf Address:11.4.4.3, Intf Id:0
Nbr Intf Address:0.0.0.0, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x48
Attribute Names: blue yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:1000000 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
IGP Id: 11.0.0.2, Network Node (OSPF 0 area 1)
Link[0]:Broadcast, DR:101.0.0.1, Nbr Node Id:4, gen:193988
Physical BW:0 (kbps), Max Reservable BW Global:0 (kbps)
Max Reservable BW Sub:0 (kbps)
Link[1]:Broadcast, DR:102.0.0.2, Nbr Node Id:5, gen:193989
Physical BW:0 (kbps), Max Reservable BW Global:0 (kbps)
Max Reservable BW Sub:0 (kbps)
IGP Id: 11.4.4.3, Network Node (OSPF 0 area 1)
Link[0]:Broadcast, DR:102.0.0.2, Nbr Node Id:5, gen:193990
Physical BW:0 (kbps), Max Reservable BW Global:0 (kbps)
Max Reservable BW Sub:0 (kbps)
Link[1]:Broadcast, DR:103.0.0.3, Nbr Node Id:6, gen:193991
Physical BW:0 (kbps), Max Reservable BW Global:0 (kbps)
Max Reservable BW Sub:0 (kbps)
Node information supplied is as for the model-type version of the command above. Ensure that expected nodes exist.
For suspect links in the topology, check:
- The type (broadcast or p2p) is correct
- The neighbor IGP-id (for p2p links) or DR (for broadcast) is correct
- The neighbor node-id is not -1 (more on this below)
- The fragment ID is correct (and consistent with what you see in the IGP topology database)
- The local interface address is correct
- The neighbor address is correct (0.0.0.0 is expected for broadcast links)
- In the case of unnumbered links, the local and neighbor interface IDs are correct
- The TE and IGP metrics are correct
- The link attributes (if any) are correct, and are resolved to the correct names if an affinity-map is configured
- The link SRLGs (if any) are correct
For broadcast links, check that the network node for the LAN exists and that the links to and from it for all routers on the LAN are correct.
If link data is wrong, check the IGP topology; if it's OK there, check the flooding on the originating router as described earlier in this document.
Neighbor node-id
The neighbor node-id is an internal mechanism used by TE. Its purpose is to help TE construct the topology and to run cSPF calculations more quickly by reducing the time it takes to find the next node in the topology when following a link. The node-ids are assigned by TE as topology nodes are learned, so they aren't predictable or deterministic. You don't need to worry about this most of the time, but there's one exception.
If you see Nbr Node Id:-1, this indicates a link that points to a node that TE doesn't know about or can't find in its topology. It's possible to see this as a transient condition when the topology is being built, but this is rare. If it persists, it indicates an error condition. If you see it:
- Check carefully to see if the node which should be on the other end of this link is, in fact, absent from the topology
- If it's missing, investigate why (check the IGP topology, and the flooding for that node).
- Frequently, the cause is simply that the neighbor on the link in question isn't running TE (which is in turn often due to config error).
SRLGs
Link SRLGs are easily examined with the show mpls traffic-eng topology srlg command, which gives one line per link/SRLG - much easier than wading through the entire topology!
Network pseudonodes never have SRLGs.
Link Attributes
Link attributes are most easily seen with the show mpls traffic-eng topology affinity command, which omits most of the other link data.
Network pseudonodes never have attributes.
Topology Filtering
It's often helpful to filter the output of the TE topology show commands to make it easier to find what you're looking for.
- The ospf and isis filters can be used to limit output to a single IGP type.
- The instance <instance> filter limits output to a single IGP instance.
- The ospf instance <instance> area <area-id> and isis instance <instance> level <level> filters limit output to a single igp-area.
- The ospf <router-id> and isis <node-id> filters restrict output to a single topology node.
- The show mpls traffic-eng topology <IP address> command limits output to nodes where:
- the node's router-id matches the supplied address
- the node has a link whose local address matches the supplied address.
Bandwidths
Link bandwidths may be inspected with the full show mpls traffic-eng topology command (with no restrictions). A brief example of the output:
IGP Id: 102.0.0.2, MPLS TE Id: 102.0.0.2 Router Node (OSPF 0 area 1)
Link[1]:Point-to-Point, Nbr IGP Id:103.0.0.3, Nbr Node Id:5, gen:194210
Frag Id:20, Intf Address:12.4.4.2, Intf Id:0
Nbr Intf Address:12.4.4.3, Nbr Intf Id:0
TE Metric:1, IGP Metric:1, Attribute Flags:0x42
Attribute Names: red yellow
Switching Capability:None, Encoding:unassigned
BC Model ID:RDM
Physical BW:155520 (kbps), Max Reservable BW Global:200000 (kbps)
Max Reservable BW Sub:100000 (kbps)
Global Pool Sub Pool
Total Allocated Reservable Reservable
BW (kbps) BW (kbps) BW (kbps)
--------------- ----------- ----------
bw[0]: 0 200000 100000
bw[1]: 0 200000 100000
bw[2]: 0 200000 100000
bw[3]: 50000 150000 100000
bw[4]: 0 150000 100000
bw[5]: 0 150000 100000
bw[6]: 0 150000 100000
bw[7]: 10000 140000 100000
- The physical bandwidth is learned by TE from the router infrastructure, and depends on the hardware of the interface itself.
- The maximum reservable bandwidths are configured under RSVP
- The allocated bandwidths at each priority are allocated to tunnels already established in the network
- The global and sub-pool reservable bandwidths are calculated according to the available bandwidth at each priority level, bearing in mind that lower-priority tunnels could be pre-empted if necessary.
Other flooding-related issues
Flooding Thresholds
When bandwidth changes occur on a link, in principle TE should flood these changes into the network to ensure other routers can carry out cSPF calculation accurately. However, when there are many tunnels, it is also desirable to suppress unnecessary updates to avoid overloading the network. Flooding thresholds are a way to address this.
Flooding thresholds are configured as a percentages of the total bandwidth available on a link. When bandwidth changes occur on a link (usually due to tunnels being admitted or going down), the local LSA information will only be regenerated and flooded immediately if the bandwidth change crosses a flooding threshold. There are separate thresholds for ingress and egress bandwidths on each link.
Flooding thresholds may be examined with the show mpls traffic-eng link-management bandwidth-allocation command. Only one link is displayed here, for brevity:
RP/0/0/CPU0:te-ma3#show mpls traffic-eng link-management bandwidth-allocation Wed Jul 28 20:59:37.093 UTC System Information:: Links Count : 8 Bandwidth Hold time : 15 seconds Link ID:: POS0/5/0/0 (12.0.0.1) Local Intf ID: 15 Link Status: Link Label Type : PSC Physical BW : 155520 kbits/sec BCID : RDM Max Reservable BW : 200000 kbits/sec (reserved: 30% in, 30% out) BC0 (Res. Global BW): 200000 kbits/sec (reserved: 30% in, 30% out) BC1 (Res. Sub BW) : 100000 kbits/sec (reserved: 0% in, 0% out) SRLGs : 20, 30 MPLS TE Link State : MPLS TE on, RSVP on, admin-up Flooded in areas : OSPF 0 area 1 Inbound Admission : allow-all Outbound Admission : allow-if-room IGP Neighbor Count : 1 BW Descriptors : 2 (including 0 BC0 descriptors) Up Thresholds : 15 30 45 60 75 80 85 90 95 96 97 98 99 100 (default) Down Thresholds : 100 99 98 97 96 95 90 85 80 75 60 45 30 15 (default) Bandwidth Information:: Downstream BC0 (kbits/sec): KEEP PRIORITY BW HELD BW TOTAL HELD BW LOCKED BW TOTAL LOCKED ------------- ---------- ------------- ---------- --------------- 0 0 0 0 0 1 0 0 0 0 2 0 0 0 0 3 0 0 50000 50000 4 0 0 0 50000 5 0 0 0 50000 6 0 0 0 50000 7 0 0 10000 60000 Downstream BC1 (kbits/sec): KEEP PRIORITY BW HELD BW TOTAL HELD BW LOCKED BW TOTAL LOCKED ------------- ---------- ------------- ---------- --------------- 0 0 0 0 0 1 0 0 0 0 2 0 0 0 0 3 0 0 0 0 4 0 0 0 0 5 0 0 0 0 6 0 0 0 0 7 0 0 0 0
Flooding thresholds may be configured with the flooding thresholds command under the interface in the main TE submode.
A consequence of flooding thresholds is that when small bandwidth changes occur on a link, these may not be immediately flooded and there may therefore be discrepancies between the link bandwidths known to TE and those flooded to the rest of the network. A comparison between the outputs of show mpls traffic-eng link-management interfaces (or show mpls traffic-eng link-management bandwidth-allocation) and show mpls traffic-eng link-management advertisements will reveal such a discrepancy, if it exists.
TE will periodically update and re-flood the local LSA to the network in each IGP-area if any change, however small, has occurred since it was last flooded; this is how small bandwidth changes are advertized to the network even if they don't cross a flooding threshold. The time remaining until this occurs is shown by the header of show mpls traffic-eng link-management advertisements:
TE will also flood immediately if admission fails on a tunnel during signaling, to ensure that the topology is up-to-date throughout the network and prevent another node repeatedly finding the same, invalid path for a tunnel.
RP/0/7/CPU0:te-ma2#show mpls tr li adv
Wed Jul 28 13:45:19.470 UTC
Flooding Status : ready
Last Flooding : 7107 seconds ago
Last Flooding Trigger : Periodic timer expired
Next Periodic Flooding In : 93 seconds
Diff-Serv TE Mode : Prestandard
Configured Areas : 2
The Next Periodic Flooding In indicates the interval until the flooding timer next expires. The period of this timer may be adjusted with the link-management timers periodic-flooding configuration command in the main TE submode.
Flooding may also be forced manually with the mpls traffic-eng link-management flood command:
RP/0/7/CPU0:te-ma2#mpls traffic-eng link-management flood Wed Jul 28 13:48:09.483 UTC RP/0/7/CPU0:te-ma2#show mpls tr li adv Wed Jul 28 13:48:16.474 UTC Flooding Status : ready Last Flooding : 7 seconds ago Last Flooding Trigger : User triggered Next Periodic Flooding In : 96 seconds Diff-Serv TE Mode : Prestandard Configured Areas : 2
Note that the reason for the last LSA update is now "User triggered".
Bandwidth Rounding
When large bandwidths are in use, small rounding errors may be observed in the flooded advertisements, so that the flooded bandwidths don't quite match the configured or calculated ones. This is a result of the conversion between integers (used in config and internally) and IEEE_FLOAT encodings (flooded).
Link bandwidths are stored as 64-bit values in TE. The relevant RFCs on flooding TE data in OSPF and IS-IS specify that flooded bandwidth are encoded as IEEE float values. When these are put into the TE topology, they are converted back into 64-bit integers in the process. This applies to locally-derived bandwidths as well as those received from other routers; they are also converted from 64-bit to IEEE-float and back to 64-bit.
Rounding errors may occur during the process with very large bandwidths. There are two things to note about this:
- The errors involved are very small compared to the link bandwidths themselves, so the likely impact is negligible
- This can't be fixed without major changes to the RSVP protocol and the relevant standards.
Example for 100GigE links
A bandwidth of 100000000000, if converted to IEEE-float and back using a web page that does this, becomes 0x51ba43b7 (IEEE) and then 9.9999998E10, which is very slightly less than what we started with.
OSPF Flooding on Broadcast Interfaces
OSPF is optimized to start advertising the DR's connection to the network pseudonode when the DR forms the first adjacency. OSPF does not stop advertising the DR's connection to the network node when DR looses its last adjacency. This is by design, and is done to reduce the number of updates the OSPF sends to TE. This means that on the DR, TE will still advertise the link in its own LSA even when there's no adjacencies over the link in question. Since the generated pseudonode for the LAN will have no links to anything else this won't cause a problem (other than unnecessarily cluttering up the topology) - but nevertheless it's perhaps not what users would expect. There are no plans to change this behavior.
Multiple Adjacencies on Broadcast Interfaces
The original TE implementation was written to run over only one IGP-area at a time. Multi-area and multi-IGP support have been added subsequently. A consequence of this is that the network type (p2p/broadcast) was originally considered to be an interface property; however, the addition of multi-area/IGP support means that this has become a property of the individual neighbor.
TE was fixed to handle different adjacency types over one interface properly in 3.8.0. In older releases, it is necessary to ensure that the network type is the same for all IGP adjacencies on the link; the best way to do this is to configure the IGP to form P2P adjacencies in all areas.
The reason for this is that LAN interfaces are usually configured back-to-back (ie p2p) in real networks, and the IGPs have optimizations which may be configured to treat these links as p2p. This means that network pseudonodes are no longer generated and flooded, which reduces the overall size and complexity of the network topology. This in turn means that less resources are used and path calculations are quicker. This benefits both the IGPs themselves and TE (if it's running over the IGP).
This doesn't affect interfaces that are P2P by default (e.g. POS) as there's no way to have broadcast adjacencies formed over them, so the issue doesn't arise.
A particular example of this is the OSPF multi-adjacency feature. In this feature, a primary adjacency is set up over the link in one area, and then other MADJ adjacencies are formed which are dependent on this. The MADJ adjacencies are always p2p; the primary adjacency, however, will be the usual type for the interface in question.
RP/0/0/CPU0:te-ma1#show run router ospf
Thu Jul 29 20:32:04.879 UTC
router ospf madj
router-id 101.1.1.1
area 0
mpls traffic-eng
interface GigabitEthernet0/2/0/1
!
!
area 1
mpls traffic-eng
multi-area-interface GigabitEthernet0/2/0/1
!
!
area 2
mpls traffic-eng
multi-area-interface GigabitEthernet0/2/0/1
!
!
area 3
mpls traffic-eng
multi-area-interface GigabitEthernet0/2/0/1
!
!
mpls traffic-eng router-id Loopback1
!
RP/0/0/CPU0:te-ma1#show run router isis
Thu Jul 29 20:32:08.677 UTC
router isis 0
net 49.0001.0011.0111.00
nsf ietf
log adjacency changes
address-family ipv4 unicast
metric-style wide
mpls traffic-eng level-1-2
mpls traffic-eng router-id Loopback1
!
interface GigabitEthernet0/2/0/1
address-family ipv4 unicast
!
!
!
In this example, GigabitEthernet0/2/0/1 has broadcast adjacencies in IS-IS level-1 and level-2 and in OSPF area 0 (the primary area for OSPF), but p2p adjacencies in the other OSPF areas:
RP/0/0/CPU0:te-ma1#show isis neighbors
Thu Jul 29 20:34:31.543 UTC
IS-IS 0 neighbors:
System Id Interface SNPA State Holdtime Type IETF-NSF
te-ma2 Gi0/2/0/1 0090.86a9.18fd Up 8 L1L2 Capable
Total neighbor count: 1
RP/0/0/CPU0:te-ma1#show ospf neighbor
Thu Jul 29 20:36:45.987 UTC
* Indicates MADJ interface
Neighbors for OSPF madj
Neighbor ID Pri State Dead Time Address Interface
102.1.1.2 1 FULL/DR 00:00:39 11.1.1.2 GigabitEthernet0/2/0/1
Neighbor is up for 00:06:38
102.1.1.2 1 FULL/ - 00:00:39 11.1.1.2 GigabitEthernet0/2/0/1*
Neighbor is up for 00:06:39
102.1.1.2 1 FULL/ - 00:00:31 11.1.1.2 GigabitEthernet0/2/0/1*
Neighbor is up for 00:06:36
102.1.1.2 1 FULL/ - 00:00:31 11.1.1.2 GigabitEthernet0/2/0/1*
Neighbor is up for 00:06:38
Total neighbor count: 4
show ospf neighbor detail gives the area for each adjacency.
This is what the link looks like in TE:
RP/0/0/CPU0:te-ma1#show mpls traffic-eng link-management interfaces GigabitEthernet0/2/0/1
Thu Jul 29 20:40:16.465 UTC
System Information::
Links Count : 9 (Maximum Links Supported 250)
Link ID:: GigabitEthernet0/2/0/1 (11.1.1.1)
Local Intf ID: 27
Link Status:
Link Label Type : PSC
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec (reserved: 0% in, 0% out)
BC0 (Res. Global BW): 200000 kbits/sec (reserved: 0% in, 0% out)
BC1 (Res. Sub BW) : 100000 kbits/sec (reserved: 0% in, 0% out)
MPLS TE Link State : MPLS TE on, RSVP on, admin-up
Inbound Admission : reject-huge
Outbound Admission : allow-if-room
IGP Neighbor Count : 6
Max Res BW (RDM) : 200000 kbits/sec
BC0 (RDM) : 200000 kbits/sec
BC1 (RDM) : 100000 kbits/sec
Max Res BW (MAM) : 500000 kbits/sec
BC0 (MAM) : 200000 kbits/sec
BC1 (MAM) : 100000 kbits/sec
Attributes : 0x0
Attribute Names :
Flooding Status: (6 area)
IGP Area[1]: OSPF madj area 3, flooded
Nbr: ID 102.1.1.2, IP 11.1.1.2 (Up)
Admin weight: not set (TE), 1 (IGP)
IGP Area[2]: OSPF madj area 2, flooded
Nbr: ID 102.1.1.2, IP 11.1.1.2 (Up)
Admin weight: not set (TE), 1 (IGP)
IGP Area[3]: OSPF madj area 1, flooded
Nbr: ID 102.1.1.2, IP 11.1.1.2 (Up)
Admin weight: not set (TE), 1 (IGP)
IGP Area[4]: OSPF madj area 0, flooded
Nbr: ID 11.1.1.2, IP 0.0.0.0 (Up)
Admin weight: not set (TE), 1 (IGP)
IGP Area[5]: IS-IS 0 level 2, flooded
Nbr: ID 0002.0002.0022.03, IP 11.1.1.2 (Up)
Admin weight: not set (TE), 10 (IGP)
IGP Area[6]: IS-IS 0 level 1, flooded
Nbr: ID 0002.0002.0022.03, IP 11.1.1.2 (Up)
Admin weight: not set (TE), 10 (IGP)
RP/0/0/CPU0:te-ma1#show mpls traffic-eng link-management igp-neighbors interface GigabitEthernet0/2/0/1
Thu Jul 29 20:43:22.687 UTC
Link ID:: GigabitEthernet0/2/0/1
Neighbor ID: 0002.0002.0022.03 (IS-IS 0 level 2, link address: 11.1.1.2)
Neighbor ID: 102.1.1.2 (OSPF madj area 2, link address: 11.1.1.2)
Neighbor ID: 11.1.1.2 (OSPF madj area 0, link address: 0.0.0.0)
Neighbor ID: 102.1.1.2 (OSPF madj area 3, link address: 11.1.1.2)
Neighbor ID: 102.1.1.2 (OSPF madj area 1, link address: 11.1.1.2)
Neighbor ID: 0002.0002.0022.03 (IS-IS 0 level 1, link address: 11.1.1.2)
And here are the advertisements for that interface. Note the difference between the areas in which the link is point-to-point (neighbor information is given) and those where it's broadcast (DR information is supplied).
RP/0/0/CPU0:te-ma1#sh mpls traffic-eng link-management advertisements
Thu Jul 29 20:45:46.243 UTC
Flooding Status : ready
Last Flooding : 10 seconds ago
Last Flooding Trigger : Periodic timer expired
Next Periodic Flooding In : 158 seconds
Diff-Serv TE Mode : Prestandard
Configured Areas : 7
IGP Area[1]:: OSPF madj area 3
Flooding Protocol : OSPF
IGP System ID : 101.1.1.1
MPLS TE Router ID : 101.1.1.1
Flooded Links : 1
Link ID:: 0 (GigabitEthernet0/2/0/1)
Link IP Address : 11.1.1.1
O/G Intf ID : 27
Neighbor : ID 102.1.1.2, IP 11.1.1.2
TE Metric : 1
IGP Metric : 1
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
IGP Area[2]:: OSPF madj area 2
Flooding Protocol : OSPF
IGP System ID : 101.1.1.1
MPLS TE Router ID : 101.1.1.1
Flooded Links : 1
Link ID:: 0 (GigabitEthernet0/2/0/1)
Link IP Address : 11.1.1.1
O/G Intf ID : 27
Neighbor : ID 102.1.1.2, IP 11.1.1.2
TE Metric : 1
IGP Metric : 1
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
IGP Area[3]:: OSPF madj area 1
Flooding Protocol : OSPF
IGP System ID : 101.1.1.1
MPLS TE Router ID : 101.1.1.1
Flooded Links : 1
Link ID:: 0 (GigabitEthernet0/2/0/1)
Link IP Address : 11.1.1.1
O/G Intf ID : 27
Neighbor : ID 102.1.1.2, IP 11.1.1.2
TE Metric : 1
IGP Metric : 1
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
IGP Area[4]:: OSPF madj area 0
Flooding Protocol : OSPF
IGP System ID : 101.1.1.1
MPLS TE Router ID : 101.1.1.1
Flooded Links : 1
Link ID:: 0 (GigabitEthernet0/2/0/1)
Link IP Address : 11.1.1.1
O/G Intf ID : 27
Designated Router : 11.1.1.2
TE Metric : 1
IGP Metric : 1
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
IGP Area[5]:: IS-IS 0 level 2
Flooding Protocol : IS-IS
IGP System ID : 0001.0011.0111
MPLS TE Router ID : 101.1.1.1
Flooded Links : 1
Link ID:: 0 (GigabitEthernet0/2/0/1)
Link IP Address : 11.1.1.1
O/G Intf ID : 27
Designated Router : 0002.0002.0022.03, IP 11.1.1.2
TE Metric : 10
IGP Metric : 10
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
IGP Area[6]:: IS-IS 0 level 1
Flooding Protocol : IS-IS
IGP System ID : 0001.0011.0111
MPLS TE Router ID : 101.1.1.1
Flooded Links : 1
Link ID:: 0 (GigabitEthernet0/2/0/1)
Link IP Address : 11.1.1.1
O/G Intf ID : 27
Designated Router : 0002.0002.0022.03, IP 11.1.1.2
TE Metric : 10
IGP Metric : 10
Physical BW : 1000000 kbits/sec
BCID : RDM
Max Reservable BW : 200000 kbits/sec
Res Global BW : 200000 kbits/sec
Res Sub BW : 100000 kbits/sec
Downstream::
Global Pool Sub Pool
----------- -----------
Reservable BW[0]: 200000 100000 kbits/sec
Reservable BW[1]: 200000 100000 kbits/sec
Reservable BW[2]: 200000 100000 kbits/sec
Reservable BW[3]: 200000 100000 kbits/sec
Reservable BW[4]: 200000 100000 kbits/sec
Reservable BW[5]: 200000 100000 kbits/sec
Reservable BW[6]: 200000 100000 kbits/sec
Reservable BW[7]: 200000 100000 kbits/sec
Attribute Flags: 0x00000000
Attribute Names:
Other topology-related issues
Effect of router-id and area changes on TE
Some network changes can, as a result of the way link-state protocols work, result in stale router node LSAs being present in the network. These can cause problems in TE's tunnel path calculations and although the network will eventually purge them, it can be difficult to repair the network in a timely manner. This section explains the problems that may occur, how to recover from them in a timely manner and how to avoid or minimize them in the first place.
LSA lifetimes
In link-state protocols, LSAs are generated by each router and flooded throughout the network. Each LSA has a lifetime, which is set by the originating router, and is periodically refreshed by the originating router. If an LSA is not refreshed for the period of its lifetime after a router last received a new version of it, that router will purge the LSA from its LSA DB. This will typically happen at around the same time for all routers in a network if a LSA is not refreshed, as LSA flooding is a rapid process.
The LSA refresh-interval and timeout are typically chosen so that one or two refreshes may be missed without an LSA being removed from the network; default refresh intervals are 20 minutes for IS-IS and 30 minutes for OSPF (assuming no changes have been made to the LSA in the meantime) and the default LSA lifetime is an hour for both IGPs. LSA generation, flooding and timeout is done independently in each area/level of the network.
Creation and effect of stale LSAs
It is possible for a router to be removed from an area in such a way that it does not have a chance to remove its own LSAs from the network. In this case, the router's generated LSAs will remain in the network until they time out and are purged.
This may occur if a router is moved from one area to another, in which case a stale LSA will remain in the old area. It may also occur if a router's IGP router ID is changed. From the point of view of the network, this looks like the sudden disappearance of one router and the creation of another.
In both these cases the router represented by the stale LSA will become unreachable as soon as its neighbors' adjacencies to it time out and those links are withdrawn from the network. This means that the IGPs' SPF calculations will be unaffected by the stale LSAs. However, TE's cSPF calculations may be affected by the stale LSAs as TE initially attempts to find the destination router-id for a tunnel in each candidate IGP-area. If this TE-router-id is present in a stale LSA, cSPF will fail as the node will still be unreachable.
In the case of intra-area tunnels or expanded loose hops in an inter-area tunnel, this may cause erroneous PCALC errors if the tunnel destination is now supposed to be unavailable; TE will report that there is no path to the destination, rather than the destination being not found.
A stale LSA may also prevent an inter-area tunnel being identified as such. TE identifies a tunnel as inter-area if its path contains at least one loose hop and its destination is not present in any local area. If the destination is found in a local area due to its presence in stale LSA, TE will not identify the tunnel as being inter-area.
Purging Stale LSAs from a Network
The first (and easiest) way to purge stale LSAs from the network is simply to wait. As explained above, they will eventually be removed. This may take up to an hour with default timer configs on all routers.
If more rapid purging is required, the only way to do this is to completely de-configure the IGP on all routers in the network, and then reconfigure it on all routers. It is essential that all routers are de-configured before any are reconfigured as otherwise the stale LSA will be re-flooded through the network by the routers that have not yet been taken down. Link-state protocols are specifically designed to ensure that every router in the network has an up-to-date and complete copy of the LSA DB.
Avoiding or Minimizing Problems
The LSA refresh interval and lifetime in OSPF are fixed to 30 and 60 minutes respectively, and cannot be changed in XR. However, in IS-IS they are both configurable, and this means that the problems caused by stale LSAs in the network can be minimized for IS-IS. This is done by shortening the LSA lifetime before any changes are made, making the appropriate changes to the network, and finally restoring the default values.
RP/0/0/CPU0:te-ma1#conf
RP/0/0/CPU0:te-ma1(config)#router isis 0
RP/0/0/CPU0:te-ma1(config-isis)#max-lsp-lifetime ?
<1-65535> Maximum LSP lifetime in seconds
RP/0/0/CPU0:te-ma1(config-isis)#max-lsp-lifetime 30 ?
level Set LSP regeneration interval for one level only
<cr>
RP/0/0/CPU0:te-ma1(config-isis)#max-lsp-lifetime 30
RP/0/0/CPU0:te-ma1(config-isis)#lsp-refresh-interval ?
<1-65535> LSP refresh time in seconds
RP/0/0/CPU0:te-ma1(config-isis)#lsp-refresh-interval 20 ?
level Set LSP refresh interval for one level only
<cr>
RP/0/0/CPU0:te-ma1(config-isis)#lsp-refresh-interval 20
RP/0/0/CPU0:te-ma1(config-isis)#commit
This configures the router to refresh its own LSAs every 20 seconds, and ensures that other routers will time them out if they're not refreshed after 30 seconds. It is only necessary to do this on the router where the major config changes are to take place. Care must be taken to avoid setting the LSA lifetime to less than the LSA refresh interval, or the network will periodically lose the node where this is done.