You can double check the node reporting 9.109 as down can telnet to port 7000 on 9.109.
Then I would restart 9.109 with -Dcassandra.load_ring_state=false added as a JVM param in cassandra-env.sh. If is still shows as down can you post the output from nodetool gossipinfo from 9.109 and the node that sees 9.109 as down. Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 18/10/2012, at 8:45 PM, Rene Kochen <rene.koc...@schange.com> wrote: > I have a four node EC2 cluster. > > Three machines show via nodetool ring that all machines are UP. > One machine shows via nodetool ring that one machine is DOWN. > > If I take a closer to the machine reporting the other machine as down, I see > the following: > > - StorageService.UnreachableNodes = 10.49.9.109 > - FailureDetector.SimpleStates: 10.49.9.109 = UP > > So gossip is fine. Actually the whole 10.49.9.109 machine is fine. I see in > the logging that there is communication between 10.49.9.109 and the machine > reporting it as down. > > How or when is a node removed from the UnreachableNodes list and reported as > UP again via nodetool ring? > > I use Cassandra 1.0.11 > > Thanks! > > Rene >