[
https://issues.apache.org/jira/browse/CASSANDRA-14957?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16748710#comment-16748710
]
Avraham Kalvo commented on CASSANDRA-14957:
-------------------------------------------
OK, after looking deep and long into this we found all of the above by
[~VincentWhite] indeed occurred for the tables which were experiencing a
certain level of data loss at the time of the rolling restart.
We decided to overcome this by preventing services from running on more than
one process at the time of running their migration flow (creation of the
schema) since we found a couple of tables which were created exactly at the
same time back then which eventually created this inconsistency discussed
above, at the time of the restart.
Later on, we'll upgrade our Cassandra deployments to enjoy from the recent
fixes having to do with this behavior.
This issue may now be closed.
Thank you all for your assistance!
Avi K
> Rolling Restart Of Nodes Causes Dataloss Due To Schema Collision
> ----------------------------------------------------------------
>
> Key: CASSANDRA-14957
> URL: https://issues.apache.org/jira/browse/CASSANDRA-14957
> Project: Cassandra
> Issue Type: Bug
> Components: Cluster/Schema
> Reporter: Avraham Kalvo
> Priority: Major
>
> We were issuing a rolling restart on a mission-critical five node C* cluster.
> The first node which was restarted got the following messages in its
> system.log:
> ```
> January 2nd 2019, 12:06:37.310 - INFO 12:06:35 Initializing
> tasks_scheduler_external.tasks
> ```
> ```
> WARN 12:06:39 UnknownColumnFamilyException reading from socket; closing
> org.apache.cassandra.db.UnknownColumnFamilyException: Couldn't find table for
> cfId bd7200a0-1567-11e8-8974-855d74ee356f. If a table was just created, this
> is likely due to the schema not being fully propagated. Please wait for
> schema agreement on table creation.
> at
> org.apache.cassandra.config.CFMetaData$Serializer.deserialize(CFMetaData.java:1336)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at
> org.apache.cassandra.db.partitions.PartitionUpdate$PartitionUpdateSerializer.deserialize30(PartitionUpdate.java:660)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at
> org.apache.cassandra.db.partitions.PartitionUpdate$PartitionUpdateSerializer.deserialize(PartitionUpdate.java:635)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at
> org.apache.cassandra.db.Mutation$MutationSerializer.deserialize(Mutation.java:330)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at
> org.apache.cassandra.db.Mutation$MutationSerializer.deserialize(Mutation.java:349)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at
> org.apache.cassandra.db.Mutation$MutationSerializer.deserialize(Mutation.java:286)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at org.apache.cassandra.net.MessageIn.read(MessageIn.java:98)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at
> org.apache.cassandra.net.IncomingTcpConnection.receiveMessage(IncomingTcpConnection.java:201)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at
> org.apache.cassandra.net.IncomingTcpConnection.receiveMessages(IncomingTcpConnection.java:178)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> at
> org.apache.cassandra.net.IncomingTcpConnection.run(IncomingTcpConnection.java:92)
> ~[apache-cassandra-3.0.10.jar:3.0.10]
> ```
> The latter was then repeated several times across the cluster.
> It was then found out that the table in question
> `tasks_scheduler_external.tasks` was created with a new schema version
> sometime along the entire cluster consecutive restart and became available
> once the schema agreement settled, which started taking requests leaving the
> previous version of the schema unavailable for any request, thus generating a
> data loss to our online system.
> Data loss was recovered by manually copying SSTables from the previous
> version directory of the schema to the new one followed by `nodetool refresh`
> to the relevant table.
> The above has repeated itself for several tables across various keyspaces.
> One other thing to mention is that a repair was in place for the first node
> to be restarted, which was obviously stopped as the daemon was shut down, but
> this doesn't seem to do with the above at first glance.
> Seems somewhat related to:
> https://issues.apache.org/jira/browse/CASSANDRA-13559
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org
For additional commands, e-mail: commits-h...@cassandra.apache.org
