11-09-2020 03:35 PM
on both switch HSRP for SVI interface for vlan 22 is keep on flapping below configuration as follows
SW1#
interface Vlan22
ip address 10.29.44.2 255.255.255.0
no ip redirects
standby 22 ip 10.29.44.1
standby 22 preempt
standby 22 authentication md5 key-chain cisco@123
end
SW2#
interface Vlan22
ip address 10.29.44.3 255.255.255.0
no ip redirects
standby 22 ip 10.29.44.1
standby 22 priority 110
standby 22 preempt
standby 22 authentication md5 key-chain cisco@123
end
logs
%DUAL-5-NBRCHANGE: EIGRP-IPv4 148: Neighbor 10.29.44.2 (Vlan22) is up: new adjacency
%DUAL-5-NBRCHANGE: EIGRP-IPv4 148: Neighbor 10.29.44.2 (Vlan22) is down: holding time expired
%DUAL-5-NBRCHANGE: EIGRP-IPv4 1: Neighbor 10.29.44.2 (Vlan22) is down: holding time expired
%DUAL-5-NBRCHANGE: EIGRP-IPv4 1: Neighbor 10.29.44.2 (Vlan22) is up: new adjacency
%DUAL-5-NBRCHANGE: EIGRP-IPv4 148: Neighbor 10.29.44.2 (Vlan22) is up: new adjacency
N%DUAL-5-NBRCHANGE: EIGRP-IPv4 1: Neighbor 10.29.44.2 (Vlan22) is down: holding time expired
%DUAL-5-NBRCHANGE: EIGRP-IPv4 148: Neighbor 10.29.44.2 (Vlan22) is down: holding time expired
: %DUAL-5-NBRCHANGE: EIGRP-IPv4 1: Neighbor 10.29.44.2 (Vlan22) is up: new adjacency
%DUAL-5-NBRCHANGE: EIGRP-IPv4 148: Neighbor 10.29.44.2 (Vlan22) is up: new adjacency
"%DUAL-6-NBRINFO: EIGRP-IPv4 148: Neighbor 10.15.164.11 (Vlan22) is blocked: not on common subnet (10.29.44.2/24)"
Need your suggestion on this to proceed further.
11-10-2020 05:21 AM
Hello,
what does 10.15.164.11 belong to ?
11-10-2020 09:27 AM
It looks to me that this post actually has 2 separate issues: 1) EIGRP neighbor relationship keeps forming and dropping 2) EIGRP neighbor not on common subnet.
I am guessing that the log messages about EIGRP neighbor dropping are from switch 2. Is that correct? The error message indicates that holding time expired. It suggests that switch 2 is receiving a hello message from switch 1, forms the neighbor relationship, but then does not receive other responses from switch 1 and takes down the neighbor relationship. It would be helpful to see logs from switch 1 at the same time that switch 2 is generating these messages. It might also be helpful to see the time stamp of the messages so that we get a sense of how quickly this is happening.
I am guessing that the log message about not on common subnet might be from switch 1. Is that correct? Is switch 2 generating similar messages? If some device in vlan 22 is sending EIGRP messages from address 10.15.164.11 then I agree with @Georg Pauwen that we need to find out what device that is.
11-10-2020 02:52 PM
hi Georg,
its SW 1 Mgm ip address (10.15.164.11 vlan 1) were i got the block msg and saying that this is not in common subnet. but i have separate subnet for Vlan 22 (10.29.44.x )
11-10-2020 10:34 PM
Please clarify which switch is generating the error message about not on common subnet.
So you are telling us that 10.15.164.11 is the address of the vlan 1 interface on sw1?
Is the connection between sw1 and sw2 access port to access port? Or is it a trunk port? Or is it a port channel? It would be helpful if you would provide some details of the configuration of both switches.
11-10-2020 10:35 AM
This message as I know when you have multi link between two same neighbor
so one is used multicast which is hello
Update is unicast but
since both use same router ID then it will not accept it and hence multi eigrp appear as flap.
solution use only one link by passive interface other link.
try this and feed me back friend
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