The masters simply use a znode in ZooKeeper to track which is which. This is a basic and fundamental mechanism that ZK provides and nothing above that is needed.
Note that you can start masters in non-active mode to enforce that you start the active on a node of your choice.
On Mar 10, 2012, at 21:04, Konrad Tendera <[EMAIL PROTECTED]> wrote:
> Hello everyone,
> While I was reading some informations about multi-Master environment I started to wondering how the "main" master is elected. As far as I know if e.g. I have 5 Masters only one is "real" Master and the rest are only backups. The main problem is that I couldn't find any larger info about whole process (i.e. how the Master is elected). Maybe You know some blogs or other resources where this issue is described (I suposse that JIRA should help me but it is hard for me to find). Thanks in advance for all your replies.