Is this desync behavior expected?

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Private Citizen

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Sep 30, 2021, 1:12:32 PM9/30/21
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I setup three nodes in a cluster using MariDB 10.6.4 and Galera-4 26.4.9
I put a value in a table, row, column. Lets say value '1'
Confirmed all 3 nodes show the value as '1'

On node 3 i turned off Galera (wsrep_on=OFF)
Restarted node 3 in stand alone and altered the value from '1' to '2'
I then turned Galera back on (wsrep_on=ON) and restarted.

Node 3 rejoined the cluster, and i was expecting to see the value i changed to '2' be changed back to '1' to be in sync with the cluster.

This did not happen, node 3 stayed '2' while nodes 1 and 2 still showed '1' as the value.
This surprised me as i expected it to sync, either the value '2' be changed to match the cluster, or the cluster change to match the newest edit.

Is this expected behavior?
(If it maters i have dirty reads on.)

Colin Charles

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Oct 4, 2021, 4:59:07 AM10/4/21
to Private Citizen, codership
Was the node desynced? You can tell from show status of course. It is not expected behaviour, no

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Private Citizen

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Oct 4, 2021, 11:07:56 AM10/4/21
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No the node was not desynced. I even did an INSERT and UPDATE query on node 1 to see if while passing those queries around the cluster it would bring node 3 "up to date". It did not. Node 3 showed the two newest queries while still having a desynced value for the one update i did while node 3 was not in wsrep=on mode. I then did an UPDATE on node 1 to the desynced row but for a different column. When node 3 got that query it then showed synced values on all of the columns of that row.
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