PXC voter vs odd numbers of nodes

[George Chilumbu]

I have seen many settings where the PXC has even number of working nodes + one voter. In my past experience i have always just setup PXC with odd number of nodes to avoid split brain.

I would like to know which one is the more idea setup, and why?

[krunal....@percona.com]

Case-1: Even number of PXC nodes + one voter (I assume by voter you mean galera arbitrator)

Case-2: Odd number of PXC nodes.

Case-1 is used when you really can't create another PXC nodes (due to resource limitation and doesn't need it too). galera arbitrator is lightweight and not a full node so can be installed on any low end machine too.

Case-2: There is no preference except that is you are dedicating a machine just for garlera arbitrator then they why not run PXC node (provided machine is of same class like other nodes else this node will act be part of critical path)

Regards,

Krunal