VRRP / VLAN arp address

[drjarmon]

End nodes ARP entries are flapping between the VRRP MAC address and the VLAN MAC address.  Each time there's a change, there's a network traffic spike.  Trying to understand why this anomaly is happening.

Thanks

[jayh · Accepted solution]

It sounds like a misconfiguration.  The physical VLAN IP must be different on each VRRP device, and the VRRP IP the same on both, also the same group number on both. 

Sample config:

Router 1

interface vlan 6

ip address 10.0.0.2 255.255.255.0

  vrrp 6 ip 10.0.0.1

Router 2

interface vlan 6

  ip address 10.0.0.3 255.255.255.0

  vrrp 6 ip 10.0.0.1

ARP for 10.0.0.2 will be that shown on router 1's VLAN interface.

ARP for 10.0.0.3 will be that shown on router 2's VLAN interface.

ARP for 10.0.0.1 will be 0000.5e00.0106 regardless of which is active.

Last byte of VRRP address is the group number.

[Anonymous]

:

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Thanks,

Levi