-decommission tablet servers
Aaron Cordova 2012-01-30, 08:33
Is there a way for a user to request that the master decommission one or more tabletservers, causing the master to migrate all the tablets away without triggering a recovery and finally shutting down the process or at least refusing to assign future tablets to it? Of course there would need to be a way to un-decommission a server too in that case.
HDFS does this for dataNodes through a list of machines in a file and a command to refreshNodes. I think it'd be better to be able to decommission servers through the monitor page, and perhaps the behaviors is: once a server is requested to be decommissioned, the master moves away tablets and the tabletserver process kills itself or the master kills it, and if a tabletserver process is started on that machine thereafter, it joins the cluster like any new server, meaning, we don't refuse that machine rejoining the cluster...