Thanks
From: Edward Capriolo [mailto:edlinuxg...@gmail.com] Sent: Thursday, November 15, 2012 4:30 PM To: user@cassandra.apache.org Subject: Re: Question regarding the need to run nodetool repair On Thursday, November 15, 2012, Dwight Smith <dwight.sm...@genesyslab.com> wrote: > I have a 4 node cluster, version 1.1.2, replication factor of 4, read/write consistency of 3, level compaction. Several questions. > > > > 1) Should nodetool repair be run regularly to assure it has completed before gc_grace? If it is not run, what are the exposures? Yes. Lost tombstones could cause deleted data to re appear. > > 2) If a node goes down, and is brought back up prior to the 1 hour hinted handoff expiration, should repair be run immediately? If node is brought up prior to 1 hour. You should let the hints replay. Repair is always safe to run. > > 3) If the hinted handoff has expired, the plan is to remove the node and start a fresh node in its place. Does this approach cause problems? > You only need to join a fresh mode if the node was down longer then gc grace. Default is 10 days. > > > Thanks > > If you read and write at quorum and run repair regularly you can worry less about the things above because they are essentially non factors.
