I think this method wasn't updated when we moved to Zookeeper (since in pre-0.20, dead master = dead cluster), also looking at when this is called, I only see it from HMerge and HBaseAdmin.isMasterRunning()... which in turn isn't called anywhere in the java code (I think we call it in the shell tho).
So we should first consider if this method is useful at all, and if so then what would be the best fix. For example, if you run a HMerge while the master is down but the region servers are up, you're going to end up with something wrong since it expects hbase to be completely down. Can you open a jira to continue discussions there? Thx! J-D On Mon, Mar 29, 2010 at 2:01 PM, Ted Yu <yuzhih...@gmail.com> wrote: > Hi, > While going over TableServers.isMasterRunning() in HConnectionManager, I see > this: > public boolean isMasterRunning() { > if (this.master == null) { > try { > getMaster(); > > } catch (MasterNotRunningException e) { > return false; > } > } > return true; > } > When isMasterRunning() is called the first time, if master is obtained > successfully, master field would contain reference to HMasterInterface. > Subsequent calls to isMasterRunning() wouldn't throw > MasterNotRunningException even if master server stops responding to clients. > > I think master.isMasterRunning() should be called if master isn't null. > > Regards >