After further review, I'm definitely going to scrub all the original nodes in the cluster.
We've lost some data as a result of this situation. It can be restored, but the question is what to do with the problematic new node first. I don't particularly care about the data that's on it, since I'm going to re-import the critical data from files anyway, and then I can recreate derivative data afterwards. So it's purely a matter of getting the cluster healthy again as quickly as possible so I can begin that import process. Any issue with running scrubs on multiple nodes at a time, provided they aren't replication neighbors? On Thu, Sep 15, 2011 at 8:18 AM, Ethan Rowe <et...@the-rowes.com> wrote: > I just noticed the following from one of Jonathan Ellis' messages > yesterday: > >> Added to NEWS: >> >> - After upgrading, run nodetool scrub against each node before running >> repair, moving nodes, or adding new ones. > > > We did not do this, as it was not indicated as necessary in the news when > we were dealing with the upgrade. > > So perhaps I need to scrub everything before going any further, though the > question is what to do with the problematic node. Additionally, it would be > helpful to know if scrub will affect the hinted handoffs that have > accumulated, as these seem likely to be part of the set of failing streams. > > On Thu, Sep 15, 2011 at 8:13 AM, Ethan Rowe <et...@the-rowes.com> wrote: > >> Here's a typical log slice (not terribly informative, I fear): >> >>> INFO [AntiEntropyStage:2] 2011-09-15 05:41:36,106 >>> AntiEntropyService.java (l >>> ine 884) Performing streaming repair of 1003 ranges with /10.34.90.8 for >>> (299 >>> >>> 90798416657667504332586989223299634,54296681768153272037430773234349600451] >>> INFO [AntiEntropyStage:2] 2011-09-15 05:41:36,427 StreamOut.java (line >>> 181) >>> Stream context metadata >>> [/mnt/cassandra/data/events_production/FitsByShip-g-1 >>> 0-Data.db sections=88 progress=0/11707163 - 0%, >>> /mnt/cassandra/data/events_pr >>> oduction/FitsByShip-g-11-Data.db sections=169 progress=0/6133240 - 0%, >>> /mnt/c >>> assandra/data/events_production/FitsByShip-g-6-Data.db sections=1 >>> progress=0/ >>> 6918814 - 0%, >>> /mnt/cassandra/data/events_production/FitsByShip-g-12-Data.db s >>> ections=260 progress=0/9091780 - 0%], 4 sstables. >>> INFO [AntiEntropyStage:2] 2011-09-15 05:41:36,428 StreamOutSession.java >>> (lin >>> e 174) Streaming to /10.34.90.8 >>> ERROR [Thread-56] 2011-09-15 05:41:38,515 AbstractCassandraDaemon.java >>> (line >>> 139) Fatal exception in thread Thread[Thread-56,5,main] >>> java.lang.NullPointerException >>> at >>> org.apache.cassandra.net.IncomingTcpConnection.stream(IncomingTcpC >>> onnection.java:174) >>> at >>> org.apache.cassandra.net.IncomingTcpConnection.run(IncomingTcpConn >>> ection.java:114) >> >> >> >> Not sure if the exception is related to the outbound streaming above; >> other nodes are actively trying to stream to this node, so perhaps it comes >> from those and temporal adjacency to the outbound stream is just >> coincidental. I have other snippets that look basically identical to the >> above, except if I look at the logs to which this node is trying to stream, >> I see that it has concurrently opened a stream in the other direction, which >> could be the one that the exception pertains to. >> >> >> On Thu, Sep 15, 2011 at 7:41 AM, Sylvain Lebresne >> <sylv...@datastax.com>wrote: >> >>> On Thu, Sep 15, 2011 at 1:16 PM, Ethan Rowe <et...@the-rowes.com> wrote: >>> > Hi. >>> > >>> > We've been running a 7-node cluster with RF 3, QUORUM reads/writes in >>> our >>> > production environment for a few months. It's been consistently stable >>> > during this period, particularly once we got out maintenance strategy >>> fully >>> > worked out (per node, one repair a week, one major compaction a week, >>> the >>> > latter due to the nature of our data model and usage). While this >>> cluster >>> > started, back in June or so, on the 0.7 series, it's been running 0.8.3 >>> for >>> > a while now with no issues. We upgraded to 0.8.5 two days ago, having >>> > tested the upgrade in our staging cluster (with an otherwise identical >>> > configuration) previously and verified that our application's various >>> use >>> > cases appeared successful. >>> > >>> > One of our nodes suffered a disk failure yesterday. We attempted to >>> replace >>> > the dead node by placing a new node at OldNode.initial_token - 1 with >>> > auto_bootstrap on. A few things went awry from there: >>> > >>> > 1. We never saw the new node in bootstrap mode; it became available >>> pretty >>> > much immediately upon joining the ring, and never reported a "joining" >>> > state. I did verify that auto_bootstrap was on. >>> > >>> > 2. I mistakenly ran repair on the new node rather than removetoken on >>> the >>> > old node, due to a delightful mental error. The repair got nowhere >>> fast, as >>> > it attempts to repair against the down node which throws an exception. >>> So I >>> > interrupted the repair, restarted the node to clear any pending >>> validation >>> > compactions, and... >>> > >>> > 3. Ran removetoken for the old node. >>> > >>> > 4. We let this run for some time and saw eventually that all the nodes >>> > appeared to be done various compactions and were stuck at streaming. >>> Many >>> > streams listed as open, none making any progress. >>> > >>> > 5. I observed an Rpc-related exception on the new node (where the >>> > removetoken was launched) and concluded that the streams were broken so >>> the >>> > process wouldn't ever finish. >>> > >>> > 6. Ran a "removetoken force" to get the dead node out of the mix. No >>> > problems. >>> > >>> > 7. Ran a repair on the new node. >>> > >>> > 8. Validations ran, streams opened up, and again things got stuck in >>> > streaming, hanging for over an hour with no progress. >>> > >>> > 9. Musing that lingering tasks from the removetoken could be a factor, >>> I >>> > performed a rolling restart and attempted a repair again. >>> > >>> > 10. Same problem. Did another rolling restart and attempted a fresh >>> repair >>> > on the most important column family alone. >>> > >>> > 11. Same problem. Streams included CFs not specified, so I guess they >>> must >>> > be for hinted handoff. >>> > >>> > In concluding that streaming is stuck, I've observed: >>> > - streams will be open to the new node from other nodes, but the new >>> node >>> > doesn't list them >>> > - streams will be open to the other nodes from the new node, but the >>> other >>> > nodes don't list them >>> > - the streams reported may make some initial progress, but then they >>> hang at >>> > a particular point and do not move on for an hour or more. >>> > - The logs report repair-related activity, until NPEs on incoming TCP >>> > connections show up, which appear likely to be the culprit. >>> >>> Can you send the stack trace from those NPE. >>> >>> > >>> > I can provide more exact details when I'm done commuting. >>> > >>> > With streaming broken on this node, I'm unable to run repairs, which is >>> > obviously problematic. The application didn't suffer any operational >>> issues >>> > as a consequence of this, but I need to review the overnight results to >>> > verify we're not suffering data loss (I doubt we are). >>> > >>> > At this point, I'm considering a couple options: >>> > 1. Remove the new node and let the adjacent node take over its range >>> > 2. Bring the new node down, add a new one in front of it, and properly >>> > removetoken the problematic one. >>> > 3. Bring the new node down, remove all its data except for the system >>> > keyspace, then bring it back up and repair it. >>> > 4. Revert to 0.8.3 and see if that helps. >>> > >>> > Recommendations? >>> > >>> > Thanks. >>> > - Ethan >>> > >>> >> >> >
