DLEP with EIGRP

Akan · ‎06-05-2020

Hi,

I am trying to utilize DLEP with the EIGRP routing algorithm.

If I query the system with "sh dlep neighbors," I see the correct CDR(Current Data Rate) for two radios connected with DLEP to the router, one having a data rate half of the other one.

If I am not mistaken, CDR is supposed to be mapped to BW for the EIGRP algorithm.

But if i look at the routing table, "sh ip route" I see the following [90/30720] vmi1, [90/30720] vmi2

where vmi1 and vmi2 are both routes with the equal metric. I would expect the EIGRP to use the DLEP CDR to calculate the best path and drop the other one. Am I wrong? It looks like it is not using the DLEP for finding the best path.

Why does it not take the CDR into account?

I would appreciate any help.

Thank you.

Here is more info that might be of help :

lab2#sh dlep neighbors

DLEP Neighbors for all interfaces:

DLEP Neighbors for Interface FastEthernet0/0
DLEP Server IP=10.0.0.3:55555 Sock=0

SID=2152 MAC_Address=b08b.cf03.4f80
Addresses:
IPv4 : 10.0.0.4
Supported Metrics:
Latency Metric : 1000 microseconds
CDR RX Metric : 41943040 bps
CDR TX Metric : 41943040 bps
MDR RX Metric : 104857600 bps
MDR TX Metric : 104857600 bps
SID=2150 MAC_Address=0253.4c56.7315
Addresses:
No Layer 3 addresses are specified.
Supported Metrics:
Latency Metric : 1000 microseconds
CDR RX Metric : 41943040 bps
CDR TX Metric : 41943040 bps
MDR RX Metric : 104857600 bps
MDR TX Metric : 104857600 bps

DLEP Neighbors for Interface FastEthernet0/1
DLEP Server IP=11.0.0.3:55555 Sock=2

SID=2153 MAC_Address=b08b.cf03.4f81
Addresses:
IPv4 : 11.0.0.4
Supported Metrics:
Latency Metric : 1000 microseconds
CDR RX Metric : 83886080 bps
CDR TX Metric : 83886080 bps
MDR RX Metric : 104857600 bps
MDR TX Metric : 104857600 bps
SID=2151 MAC_Address=0253.4c56.6527
Addresses:
No Layer 3 addresses are specified.
Supported Metrics:
Latency Metric : 1000 microseconds
CDR RX Metric : 83886080 bps
CDR TX Metric : 83886080 bps
MDR RX Metric : 104857600 bps
MDR TX Metric : 104857600 bps

lab2#sh ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
a - application route
+ - replicated route, % - next hop override, p - overrides from PfR

Gateway of last resort is not set

10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
C 10.0.0.0/24 is directly connected, FastEthernet0/0
L 10.0.0.3/32 is directly connected, FastEthernet0/0
C 10.0.0.4/32 is directly connected, vmi1
11.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
C 11.0.0.0/24 is directly connected, FastEthernet0/1
L 11.0.0.3/32 is directly connected, FastEthernet0/1
C 11.0.0.4/32 is directly connected, vmi2
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/24 is directly connected, Vlan1
L 192.168.1.5/32 is directly connected, Vlan1
D 192.168.2.0/24 [90/30720] via 11.0.0.4, 00:04:30, vmi2
[90/30720] via 10.0.0.4, 00:04:30, vmi1

lab2#sh vmi neighbors detail

2 vmi1 Neighbors
2 vmi2 Neighbors
4 Total Neighbors

vmi1 IPV6 Address=::
IPV6 Global Addr=::
IPV4 Address=10.0.0.4, Uptime=00:02:15
Output pkts=18, Input pkts=0
METRIC DATA: Total rcvd=1, Avg arrival rate (ms)=0
CURRENT: MDR=104857600 bps, CDR=41943040 bps
Lat=1 ms, Res=0, RLQ=0, load=0
MDR Max=104857600 bps, Min=104857600 bps, Avg=104857600 bps
CDR Max=41943040 bps, Min=41943040 bps, Avg=41943040 bps
Latency Max=1, Min=1, Avg=1 (ms)
Resource Max=0%, Min=0%, Avg=0%
RLQ Max=0, Min=0, Avg=0
Load Max=0%, Min=0%, Avg=0%
Transport DLEP, Session ID=2152

vmi1 IPV6 Address=::
IPV6 Global Addr=::
IPV4 Address=0.0.0.0, Uptime=00:02:15
Output pkts=0, Input pkts=0
METRIC DATA: Total rcvd=1, Avg arrival rate (ms)=0
CURRENT: MDR=104857600 bps, CDR=41943040 bps
Lat=1 ms, Res=0, RLQ=0, load=0
MDR Max=104857600 bps, Min=104857600 bps, Avg=104857600 bps
CDR Max=41943040 bps, Min=41943040 bps, Avg=41943040 bps
Latency Max=1, Min=1, Avg=1 (ms)
Resource Max=0%, Min=0%, Avg=0%
RLQ Max=0, Min=0, Avg=0
Load Max=0%, Min=0%, Avg=0%
Transport DLEP, Session ID=2150

vmi2 IPV6 Address=::
IPV6 Global Addr=::
IPV4 Address=11.0.0.4, Uptime=00:02:15
Output pkts=19, Input pkts=0
METRIC DATA: Total rcvd=1, Avg arrival rate (ms)=0
CURRENT: MDR=104857600 bps, CDR=83886080 bps
Lat=1 ms, Res=0, RLQ=0, load=0
MDR Max=104857600 bps, Min=104857600 bps, Avg=104857600 bps
CDR Max=83886080 bps, Min=83886080 bps, Avg=83886080 bps
Latency Max=1, Min=1, Avg=1 (ms)
Resource Max=0%, Min=0%, Avg=0%
RLQ Max=0, Min=0, Avg=0
Load Max=0%, Min=0%, Avg=0%
Transport DLEP, Session ID=2153

vmi2 IPV6 Address=::
IPV6 Global Addr=::
IPV4 Address=0.0.0.0, Uptime=00:02:15
Output pkts=0, Input pkts=0
METRIC DATA: Total rcvd=1, Avg arrival rate (ms)=0
CURRENT: MDR=104857600 bps, CDR=83886080 bps
Lat=1 ms, Res=0, RLQ=0, load=0
MDR Max=104857600 bps, Min=104857600 bps, Avg=104857600 bps
CDR Max=83886080 bps, Min=83886080 bps, Avg=83886080 bps
Latency Max=1, Min=1, Avg=1 (ms)
Resource Max=0%, Min=0%, Avg=0%
RLQ Max=0, Min=0, Avg=0
Load Max=0%, Min=0%, Avg=0%
Transport DLEP, Session ID=2151

Giuseppe Larosa · ‎06-07-2020

Hello @Akan ,

with default K values EIGRP use delay and bandwidth to calculate its composite 32 bit integer metric.

However, the bandwidth parameter that EIGRP looks for is not the effective line speed of an interface but the bandwidth parameter that we can see in

show interface type x/y

Being this bandwidth an administrative parameter it does not reflect the effective speed of an interface.

See the following document on configuring DLEP according to RFC 8175

https://www.cisco.com/c/en/us/td/docs/wireless/outdoor_industrial/iw3702/technote/b_DLEP_RFC8175.html?dtid=osscdc000283

There is also a section about EIGRP

router eigrp 100
 metric weights 0 1 0 1 0 1
 traffic-share min across-interfaces
 network 2.2.2.2 0.0.0.0
 network 100.100.1.0 0.0.0.255
 network 100.100.2.0 0.0.0.255
 neighbor 100.100.1.2 vmi1
 neighbor 100.100.2.2 vmi2
 eigrp router-id 2.2.2.2

Please note that if you change the metric weights you need to do the same change on all routers to build an EIGRP adjacency.

Hope to help

Giuseppe

Akan · ‎06-07-2020

Hi @Giuseppe Larosa

Thank you for your reply.

"However, the bandwidth parameter that EIGRP looks for is not the effective line speed of an interface but the bandwidth parameter"

I agree with you. I have already noticed that it is using the bandwidth.

For example,

Default metric weight K1=1, K2=0, K3=1, K4=0, K5=0 so only bandwidth and delay are used for calculation.

10.0.0.4 (vmi1), from 10.0.0.4, Send flag is 0x0

Minimum bandwidth is 100000 Kbit
Total delay is 200 microseconds

10^7 / 100000 = 100

200 / 10 = 20

(100+20) * 256 = 30720

D 192.168.2.0/24 [90/30720] via 11.0.0.4, 00:04:30, vmi2
[90/30720] via 10.0.0.4, 00:04:30, vmi1

which shows that in the calculation the bandwidth is being used.

But also according to the document you linked :

The link metrics of VMI interface map to the basic EIGRP interface parameters according to the following mapping table:

VMI EIGRP

current data rate bandwidth

relative link quality resources reliability

latency delay

load load

If understand this correctly CDR is supposed to be used in the place of bandwidth. Am I misinterpreting this? If not how can I make use of the CDR value reported by the DLEP?

I have been using the default metric. I think it should work for me since my DLEP client is only reporting the CDR. RLQ and Latency are not even being reported so I cannot use them.

So my metric should be

metric weights 0 1 0 1 0 0

which is the default metric.

Thanks,

Hakan

Akan · ‎06-07-2020

Hi @Giuseppe Larosa

Thanks for your reply. I sent another reply but I think it got stuck to spam filter.

I have already noticed that it is using the BW instead of CDR for the calculation.

"Being this bandwidth an administrative parameter it does not reflect the effective speed of an interface."

But according to the document you linked :
"The link metrics of VMI interface map to the basic EIGRP interface parameters according to the following mapping table:"

current data rate --> bandwidth

relative link quality resources -->reliability
latency -->delay
load -->load

If I understand this correctly, CDR is mapped to the BW. But I am not seeing this.

My question is how do get the EIGRP algorithm to use my CDR? Please note that my DLEP client does not report RLQ or Latency(hence I use default EIGRP map). So I have only one parameter with which to influence the routing.

Thanks.

Giuseppe Larosa · ‎06-07-2020

Hello @Akan ,

you are right the table reports a mapping between vmi parameters and EIGRP metric components.

The document has also a pointer to a document about wide EIGRP metric that is the new metric of EIGRP named mode

https://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/enhanced-interior-gateway-routing-protocol-eigrp/whitepaper_C11-720525.html#_Toc443979294

I wonder if you need to use EIGRP named mode in order to make your configuration to work.

It can be an IOS version issue.

You can use

show eigrp plugin

to see what version of EIGRP is present in your router.

Hope to help

Giuseppe

Akan · ‎06-07-2020

@Giuseppe Larosa

Here is the output. I think I need to enable manet somehow. I do not see any extra parameter.

lab1#show eigrp plugin
EIGRP feature plugins:::
eigrp-release : 23.00.00 : Portable EIGRP Release
: 2.00.15 : Source Component Release(rel23)
parser : 2.02.00 : EIGRP Parser Support
igrp2 : 2.00.00 : Reliable Transport/Dual Database
manet : 3.00.00 : Mobile ad-hoc network (MANET)
bfd : 2.00.00 : BFD Platform Support
eigrp-pfr : 1.00.01 : Performance Routing Support
EVN/vNets : 1.00.00 : Easy Virtual Network (EVN/vNets)
ipv4-af : 2.01.01 : Routing Protocol Support
ipv4-sf : 1.02.00 : Service Distribution Support
ipv6-af : 2.01.01 : Routing Protocol Support
ipv6-sf : 2.01.00 : Service Distribution Support
vNets-parse : 1.00.00 : EIGRP vNets Parse Support
snmp-agent : 2.00.00 : SNMP/SNMPv2 Agent Support

My IOS is

Cisco IOS Software, C5915 Software (C5915-ADVENTERPRISEK9-M), Version 15.7(3)M6, RELEASE SOFTWARE (fc1)

Giuseppe Larosa · ‎06-08-2020

Hello @Akan ,

I agree with you.

in EIGRP named mode you have address families and you might find a section for manet so I would suggest to try to use named mode EIGRP to see if behaviour changes.

Hope to help

Giuseppe