GARP For Non Ethernet assigned IP addresses
24578
Created On 04/10/19 09:25 AM - Last Modified 02/02/21 06:24 AM
Symptom
When HA failover happens, The new active PA sends Gratuitous ARP (GARP) to update L2 and ARP table of neighboring devices. These GARP are for actual dataplane (DP) interface IP address only. For Non-DP interface IPs like loopback IP and NAT addresses, the PA do not send GARP.
Environment
In the case of VM series with "Use Hypervisor Assigned MAC Addresses" and having Non-DP IP that falls into the interface's subnet, it is recommended to either.
1- Configure Non-DP interface IPs as a secondary IP on DP interfaces
OR
2- Make sure Non-DP interface IPs doesn't fall into DP interface's subnet and use static or dynamic routing on the neighbor network device
In order to avoid the risk of packets drop until TTL for ARP cache expired on the neighbor network device after an HA failover