05-29-2014 02:13 PM
I am planning on migrating a pair of our ADX's from Layer 2 code to Layer 3 code to support our changing environment. I was planning on upgrading the standby to Layer 3 code and making the configuration changes necessary. I am worried that both ADX's will try and become active for the same VIP's once the Layer 3 ADX is configured. When one ADX is running Layer 2 code and one is running Layer 3 code will they be able to negotiate the active ADX based on sym-priority? Has anyone gone through this process that could give me some advice?
06-17-2014 04:28 PM - edited 06-17-2014 04:35 PM
L2 and L3 build HA is not "officially" supported and its recommended that both ADX should have same code version. However "technically" both the ADX "may" be able to negotiate the sym priority provided that they are l2 reachable.
Assign the VIPs on L3 code a low sym-priority so that when it comes up its in standby mode also one other thing I think that can help is configuring the "server sym-pdu-rate" which controls how much time standby side will wait before declaring itself as active, on not receiving any packets from Active box.
You can try configuring a large value for the server sym-pdu-rate so that the standby box remains in that state for longer time in case communication is failed.