In case of recent EIGRP set up , there could also be a state of affairs when of exterior routes should not being learnt by EIGRP Routers. Let’s perceive one such state of affairs of Redistributed EIGRP Routes not learnt, and learn how to resolve this drawback situation.
Situation: Redistributed EIGRP Routes not learnt because of similar Router ID
Beneath diagram exhibits 4 Routers (R1, R2, R3 and R4) linked to one another in a line with R1, R2 and R3 working EIGRP in AS 1 whereas R3 and R4 are a part of exterior area utilizing static Routes to succeed in the networks.
The IP deal with and Interface particulars for every gadget is given in under desk for reference –
Configuration Output
The output of “Present ip route eigrp” on R2 exhibits all of the EIGRP discovered routes –
R2#present ip route eigrp
1.0.0.0/24 is subnetted, 1 subnets
D 1.1.1.0 [90/409600] by way of 192.168.12.1, 00:58:07, FastEthernet0/0
D 3.0.0.0/8 [90/409600] by way of 192.168.23.3, 00:53:41, FastEthernet0/1
4.0.0.0/24 is subnetted, 1 subnets
D EX 4.4.4.0 [170/2560025856] by way of 192.168.23.3, 00:55:06, FastEthernet0/1
D EX 192.168.34.0/24
[170/2560025856] by way of 192.168.23.3, 00:55:38, FastEthernet0/1
As per above output , exterior networks 4.4.4.0/24 and 192.168.23.0/24 are being learnt by way of EIGRP on R2.
The identical command “present ip route eigrp” is issued on R1 and output is under –
R1#present ip route eigrp
2.0.0.0/24 is subnetted, 1 subnets
D 2.2.2.0 [90/409600] by way of 192.168.12.2, 00:56:44, FastEthernet0/0
D 3.0.0.0/8 [90/435200] by way of 192.168.12.2, 00:56:10, FastEthernet0/0
D 192.168.23.0/24 [90/307200] by way of 192.168.12.2, 01:00:33, FastEthernet0/0
Notable right here is that R1 shouldn’t be receiving the identical the exterior routes “4.4.4.0/24” and “192.168.34.0/24”.
Now we surprise what went flawed as a result of EIGRP default behaviour is to promote the Routes learnt from neighbor i.e. R2 ought to promote to R1.
To be able to troubleshoot , we challenge the command “present ip eigrp topology” for exterior routes on R2 –
R2#sh ip eigrp topology 4.4.4.0/24
IP-EIGRP (AS 1): Topology entry for 4.4.4.0/24
State is Passive, Question origin flag is 1, 1 Successor(s), FD is 2560025856
Routing Descriptor Blocks:
192.168.23.3 (FastEthernet0/1), from 192.168.23.3, Ship flag is 0x0
Composite metric is (2560025856/2560000256), Route is Exterior
Vector metric:
Minimal bandwidth is 1 Kbit
Whole delay is 1010 microseconds
Reliability is 1/255
Load is 1/255
Minimal MTU is 1
Hop rely is 1
Exterior knowledge:
Originating router is 1.1.1.1
AS variety of route is 0
Exterior protocol is Static, exterior metric is 0
Administrator tag is 0 (0x00000000)
R2#present ip eigrp topology 192.168.34.0/24
IP-EIGRP (AS 1): Topology entry for 192.168.34.0/24
State is Passive, Question origin flag is 1, 1 Successor(s), FD is 2560025856
Routing Descriptor Blocks:
192.168.23.3 (FastEthernet0/1), from 192.168.23.3, Ship flag is 0x0
Composite metric is (2560025856/2560000256), Route is Exterior
Vector metric:
Minimal bandwidth is 1 Kbit
Whole delay is 1010 microseconds
Reliability is 1/255
Load is 1/255
Minimal MTU is 1
Hop rely is 1
Exterior knowledge:
Originating router is 1.1.1.1
AS variety of route is 0
Exterior protocol is linked, exterior metric is 0
Administrator tag is 0 (0x00000000)
From above output on R2 , we see the originating Router of Exterior Router ID of routes is “1.1.1.1” which is R3.
This makes us surprise what’s the Router ID of R1. The output to view R1 RID is –
R1#sh ip eigrp topology | embrace ID
IP-EIGRP Topology Desk for AS(1)/ID(1.1.1.1)
As understood from troubleshooting , R1 and R3 each have the identical Router ID therefore exterior Routes should not being learnt by R1. So we have to change the Router ID of both R1 or R3. Lets change the RID of R3 and see what occurs –
R3#config t
Enter configuration instructions, one per line. Finish with CNTL/Z.
R3(config)#router eigrp 1
R3(config-router)#eigrp router-id 3.3.3.3
As soon as the RID of R3 is modified now R1 ought to have the ability to set up exterior routes and the identical is proven under –
R1#present ip route eigrp
2.0.0.0/24 is subnetted, 1 subnets
D 2.2.2.0 [90/409600] by way of 192.168.12.2, 01:11:15, FastEthernet0/0
D 3.0.0.0/8 [90/435200] by way of 192.168.12.2, 00:02:15, FastEthernet0/0
4.0.0.0/24 is subnetted, 1 subnets
D EX 4.4.4.0 [170/2560051456] by way of 192.168.12.2, 00:02:15, FastEthernet0/0
D 192.168.23.0/24 [90/307200] by way of 192.168.12.2, 01:15:03, FastEthernet0/0
D EX 192.168.34.0/24
[170/2560051456] by way of 192.168.12.2, 00:02:15, FastEthernet0/0
Hope this troubleshooting state of affairs helped the viewers. Kindly share your ideas and assist in case we’re required to additional refine the doc.
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Configuring EIGRP Stub Function
