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https://issues.apache.org/jira/browse/CASSANDRA-20118?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17904865#comment-17904865
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Stefan Miklosovic commented on CASSANDRA-20118:
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??The different digest was due to new table properties (specifically
allow_auto_snapshot and incremental_backups) that weren't present in 4.1. This
is also bad news because there will have to be a schema disagreement at some
point, since these fundamentally change the digest calculation.??
yes, this is what I was mentioning in my first comment
??EDIT: Actually I am not completely sure it is so simple like that, for
example, if we introduce a new table property into CQL (all these properties on
CQL specified with WITH clause), that itself would change the schema version
while schema of a table as such (columns etc) would stay intact.??
Isn't there really any workaround? Hard to live with this!
It is about how we de/serialize in TableParams.Serializer, we are already
dealing with "versions" and conditionally setting these two ...
> Hints ignored during Upgrade from C*4 to C*5
> --------------------------------------------
>
> Key: CASSANDRA-20118
> URL: https://issues.apache.org/jira/browse/CASSANDRA-20118
> Project: Apache Cassandra
> Issue Type: Bug
> Components: Consistency/Hints
> Reporter: Paul Chandler
> Assignee: Brandon Williams
> Priority: Normal
> Fix For: 5.0.x
>
> Attachments: 4-1debug-third-node.log, 4-1debug.log,
> 4-1system-third-node.log, 4-1system.log, 5-0debug.log, 5-0system.log,
> system-20118.log
>
>
> I have discovered that some hints were not being processed after nodes come
> back up when a cluster in in a mixed mode with some cassandra 4 nodes and
> some cassdandra 5 nodes ( these with a storage compatibility mode CASSANDRA_4
> )
>
> When in this mode there is a schema mismatch after the first node has been
> upgraded, which continues until the last node has been upgraded.
> It seems that the hints are blocked from being sent if there is a schema
> mismatch between the 2 nodes, that can be seen at this line.
> [cassandra/src/java/org/apache/cassandra/hints/HintsDispatchTrigger.java at
> cassandra-5.0 ·
> apache/cassandra|https://github.com/apache/cassandra/blob/cassandra-5.0/src/java/org/apache/cassandra/hints/HintsDispatchTrigger.java#L65]
> I have tested removing this line, and that then does allow the hint to be
> transferred normally. However I am not sure of the implications for doing
> that if the hint is for part of the schema where the actual mismatch occurs.
>
> This creates the problem when a node is being upgraded and is currently down,
> hint files will be created for it on the new cassandra 5 nodes and the old
> cassandra 4 nodes, but the hint files on the old cassandra 4 nodes will not
> be processed, due to the schema mismatch. Leading to potential data loss.
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