04-26-2016 12:31 PM
hello everybody,
i am using GNS3 1.4.5 .. IOU image to create a simple MPLS lab.
routes are propagated via OSPF and pingable, but show mpls forwarding-table gives me below output.
P-11#show mpls forwarding-table
Local Outgoing Prefix Bytes Label Outgoing Next Hop
Label Label or Tunnel Id Switched interface
16 No Label 10.1.1.1/32 0 Et0/0.111 10.1.111.1
17 No Label 10.1.109.0/24 0 Et0/0.111 10.1.111.1
18 No Label 10.1.104.0/24 0 Et0/0.111 10.1.111.1
19 No Label 10.1.101.0/24 0 Et0/0.111 10.1.111.1
20 No Label 10.1.10.10/32 0 Et0/0.111 10.1.111.1
04-27-2016 05:15 AM
Hello Mohammad,
Do we have any LDP neighborships established on P-11? Can you paste your interface configurations as well as the following output:
- sh mpls ldp neighborship
- sh mpls ldp discovery
- sh mpls ldp bindings
Thx,
Victor Hugo Acevedo
04-28-2016 04:10 AM
here is your request, and be noted that ldp neighborship is not established between any two P routers.
configuration
===========
ip cef
!
mpls label protocol ldp
mpls ldp discovery hello interval 1
!
interface Loopback0
ip address 10.1.11.11 255.255.255.255
!
interface Ethernet0/0
no ip address
mpls ip
!
interface Ethernet0/0.111
encapsulation dot1Q 111
ip address 10.1.111.11 255.255.255.0
mpls ip
!
interface Ethernet0/0.112
encapsulation dot1Q 112
ip address 10.1.112.11 255.255.255.0
mpls ip
!
interface Ethernet0/0.113
encapsulation dot1Q 113
ip address 10.1.113.11 255.255.255.0
mpls ip
!
!
router ospf 1
router-id 10.1.11.11
network 10.1.0.0 0.0.255.255 area 0
!
mpls ldp router-id Loopback0
!
Status
======
P-11#show mpls ldp nei
P-11#show mpls ldp dis
P-11#show mpls ldp discovery
Local LDP Identifier:
10.1.11.11:0
Discovery Sources:
Interfaces:
Ethernet0/0 (ldp): xmit
Ethernet0/0.111 (ldp): xmit
Ethernet0/0.112 (ldp): xmit
Ethernet0/0.113 (ldp): xmit
P-11#show mpls ldp bin
P-11#show mpls ldp bindings
lib entry: 10.1.1.1/32, rev 15
local binding: label: 20
lib entry: 10.1.10.10/32, rev 13
local binding: label: 19
lib entry: 10.1.11.11/32, rev 11
local binding: label: imp-null
lib entry: 10.1.101.0/24, rev 21
local binding: label: 23
lib entry: 10.1.104.0/24, rev 19
local binding: label: 22
lib entry: 10.1.109.0/24, rev 17
local binding: label: 21
lib entry: 10.1.111.0/24, rev 7
local binding: label: imp-null
lib entry: 10.1.112.0/24, rev 8
local binding: label: imp-null
lib entry: 10.1.113.0/24, rev 9
local binding: label: imp-null
P-11#show mpls fo
P-11#show mpls forwarding-table
Local Outgoing Prefix Bytes Label Outgoing Next Hop
Label Label or Tunnel Id Switched interface
19 No Label 10.1.10.10/32 0 Et0/0.111 10.1.111.1
20 No Label 10.1.1.1/32 0 Et0/0.111 10.1.111.1
21 No Label 10.1.109.0/24 0 Et0/0.111 10.1.111.1
22 No Label 10.1.104.0/24 0 Et0/0.111 10.1.111.1
23 No Label 10.1.101.0/24 0 Et0/0.111 10.1.111.1
P-11#
04-28-2016 06:25 AM
Hello Mohammad,
Yes, it seems that is our problem here. Without LDP neighborships we will not receive labels. Can we make sure we have routes for the /32 Loopback addresses of our other devices?
It seems that we are transmitting LDP hellos but never receive anything from our peers. Please make sure they also have "mpls ip" enable don the interfaces and have /32 loopback addresses and have a route back to our /32 loopback address.
P-11#show mpls ldp discovery
Local LDP Identifier:
10.1.11.11:0
Discovery Sources:
Interfaces:
Ethernet0/0 (ldp): xmit <<<< Transmit only,
Ethernet0/0.111 (ldp): xmit <<< Nothing is being received
Ethernet0/0.112 (ldp): xmit <<<
Ethernet0/0.113 (ldp): xmit <<<
Thx,
Victor Hugo Acevedo
05-01-2016 08:45 PM
Dear Victor,
sorry for late answer, i was checking the lab with colleagues.
i cannot see anything wrong; OSPF is propagating routes perfectly and they are pingable; also, mpls ip is enabled globaly, on main interface, and on subinterfaces.
P-01#show ip route ospf
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 11 subnets, 2 masks
O 10.1.10.10/32 [110/11] via 10.1.101.10, 00:01:46, Ethernet0/0.101
O 10.1.11.11/32 [110/11] via 10.1.111.11, 00:01:56, Ethernet0/0.111
O 10.1.104.0/24 [110/20] via 10.1.101.10, 00:01:46, Ethernet0/0.101
O 10.1.109.0/24 [110/20] via 10.1.101.10, 00:01:46, Ethernet0/0.101
O 10.1.112.0/24 [110/20] via 10.1.111.11, 00:01:56, Ethernet0/0.111
O 10.1.113.0/24 [110/20] via 10.1.111.11, 00:01:56, Ethernet0/0.111
P-01#ping 10.1.10.10 re 2 size 1500
Type escape sequence to abort.
Sending 2, 1500-byte ICMP Echos to 10.1.10.10, timeout is 2 seconds:
!! <<< indicates back routes are working fine
Success rate is 100 percent (2/2), round-trip min/avg/max = 2/2/2 ms
P-01#ping 10.1.11.11 re 2 size 1500
Type escape sequence to abort.
Sending 2, 1500-byte ICMP Echos to 10.1.11.11, timeout is 2 seconds:
!! <<< indicates back routes are working fine
Success rate is 100 percent (2/2), round-trip min/avg/max = 2/2/2 ms
P-01#
I believe the problem is in GNS3.
moreover, UNL loads routers, and then they stop; IOU-Web v2.0 do not load labs, but v22.0 is working fine.
i tried 7200 images and IOU L3 images.
My problem is in simulation. did you see this problem before?!!!!
05-02-2016 06:05 AM
Hey Mohammad,
It could be a GNS3 problem. Does the image/licenses used support MPLS on these routers? Just to rule out a configuration problem, Can you paste the following from P-01 router
- sh mpls ldp neighborship
- sh mpls ldp discovery
Thx,
Victor Hugo Acevedo
05-03-2016 10:16 PM
Hew Victor,
1st regarding show commands, it shows the same exact output of P-11 posted above, except for interface names.
2nd regarding license, YES.
3rd regarding simulation, not only GNS3, but also many simulators misbehave with me, although i am using a Core-i7 labtop.
05-04-2016 04:56 AM
Hey Mohammad,
So it shows it is only seeing "xmit" only and no rcv?
Can you try one last thing for me? Can you please ping from P-01 from P-11, sourcing it from it's loopback interface? and vice versa?
Also, remove "mpls ip" from Eth0/0 physical interface. We only need this on the subinterfaces.
Thx,
Victor Hugo Acevedo
05-06-2016 02:27 AM
Hey Victor,
thanks for you patience. below is your requested Ping:
P-01#ping 10.1.11.11 source 10.1.1.1 size 1500 repeat 22
Type escape sequence to abort.
Sending 22, 1500-byte ICMP Echos to 10.1.11.11, timeout is 2 seconds:
Packet sent with a source address of 10.1.1.1
!!!!!!!!!!!!!!!!!!!!!!
Success rate is 100 percent (22/22), round-trip min/avg/max = 1/2/6 ms
also, i did the following changes:
i removed mpls ip from the physical interface
i hard-coded duplex of E0/0 on all P-xx routers
no change in LDP neighborship or discovery.
P-01#show mpls ldp dis
Local LDP Identifier:
10.1.1.1:0
Discovery Sources:
Interfaces:
Ethernet0/0.101 (ldp): xmit
Ethernet0/0.111 (ldp): xmit
After all, thanks for your long support.
it seems my Laptop doesn't handle simulation well as i faced many troubles with Juniper Mx and SRX series. anso, UNL is not working fine with me. I mayy try another machine and feed you back if you wish.
05-06-2016 02:39 AM
one last-thing
below is my physical topology, if it makes sense
05-06-2016 04:51 AM
Hey Mohammad,
Not a problem. That is interesting, do you see this same issue if you connect the routers back to back, omitting the switch in the middle?
Thx,
Victor Hugo Acevedo
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