Adding new gateway and cluster configuration to existing 1.4 router

Hi all

As the title suggests, I’m asking for information on best practices and possible pitfalls on adding a new vyOS router to an existing network for network reliability, failover and high availability.

I have a few clear ideas about what needs doing (cluster network subnet, cluster configuration, selecting primary and secondary gateways, modifying dhcp management for all client subnets, etc)

What should I look out for and what’s the best way to do it without breaking the network?

Thanks a lot in advance.