2013-09-01 05:59:27,792 [main-EventThread] INFO (org.I0Itec.zkclient.ZkClient) - zookeeper state changed (Disconnected) 2013-09-01 05:59:27,692 [main-SendThread( mandm-zookeeper-asg.data.sfdc.net:2181)] INFO (org.apache.zookeeper. ClientCnxn) - Client session timed out, have not heard from server in 4002ms for sessionid 0x140c603da5b0032, closing socket connection and attempting reconnect
This indicates that your mirror maker and/or your zookeeper cluster is GCing for long periods of time. I have observed that if "client session timed out" happens too many times, the client tends to lose zookeeper watches. This is a potential bug in zookeeper. If this happens, your mirror maker instance might not rebalance correctly and will start losing data. You mentioned consumption/production stopped on your mirror maker, could you please take a thread dump and point us to it? Meanwhile, you might want to fix the GC pauses. Thanks, Neha On Tue, Sep 3, 2013 at 8:59 AM, Rajasekar Elango <rela...@salesforce.com>wrote: > We found that mirrormaker stopped consuming and producing over the week end > (09/01). Just seeing "Client session timed out" messages in mirrormaker > log. I restarted to it today 09/03 to resume processing. Here is the logs > line in reverse order. > > > 2013-09-03 14:20:40,918 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.utils.VerifiableProperties) - Verifying properties > 2013-09-03 14:20:40,877 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ZookeeperConsumerConnector) - > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506], > begin rebalancing consumer > mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506 try #1 > 2013-09-03 14:20:38,877 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ZookeeperConsumerConnector) - > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506], > Committing all offsets after clearing the fetcher queues > 2013-09-03 14:20:38,877 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ZookeeperConsumerConnector) - > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506], > Cleared the data chunks in all the consumer message iterators > 2013-09-03 14:20:38,877 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ZookeeperConsumerConnector) - > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506], > Cleared all relevant queues for this fetcher > 2013-09-03 14:20:38,877 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ConsumerFetcherManager) - > [ConsumerFetcherManager-1378218012760] All connections stopped > 2013-09-03 14:20:38,877 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ConsumerFetcherManager) - > [ConsumerFetcherManager-1378218012760] Stopping all fetchers > 2013-09-03 14:20:38,877 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ConsumerFetcherManager) - > [ConsumerFetcherManager-1378218012760] Stopping leader finder thread > 2013-09-03 14:20:38,877 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ZookeeperConsumerConnector) - > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506], > Rebalancing attempt failed. Clearing the cache before the next rebalancing > operation is triggered > 2013-09-03 14:20:38,876 > > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506_watcher_executor] > INFO (kafka.consumer.ZookeeperConsumerConnector) - > [mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506], end > rebalancing consumer > mirrormakerProd_ops-mmrs1-1-asg.ops.sfdc.net-1378218012575-6779d506 try #0 > 2013-09-01 05:59:29,069 [main-SendThread( > mandm-zookeeper-asg.data.sfdc.net:2181)] INFO > (org.apache.zookeeper.ClientCnxn) - Socket connection established to > mandm-zookeeper-asg.data.sfdc.net/10.228.48.38:2181, initiating session > 2013-09-01 05:59:29,069 [main-SendThread( > mandm-zookeeper-asg.data.sfdc.net:2181)] INFO > (org.apache.zookeeper.ClientCnxn) - Opening socket connection to server > mandm-zookeeper-asg.data.sfdc.net/10.228.48.38:2181 > 2013-09-01 05:59:27,792 [main-EventThread] INFO > (org.I0Itec.zkclient.ZkClient) - zookeeper state changed (Disconnected) > 2013-09-01 05:59:27,692 [main-SendThread( > mandm-zookeeper-asg.data.sfdc.net:2181)] INFO > (org.apache.zookeeper.ClientCnxn) - Client session timed out, have not > heard from server in 4002ms for sessionid 0x140c603da5b0032, closing socket > connection and attempting reconnect > > > As you can see, no log lines appeared after 2013-09-01 05:59:29. I checked > lag using consumerOffsetChecker and observed that log size and lag is > growing, but offset of mirrormaker remains same. We have two mirrormaker > process running and both of them had same issue during same time frame.. > Any hint on what could be problem..? How do we go about trouble shooting > this..? > > Thanks in advance.. > > -- > Thanks, > Raja. >