Fix duplicate service messages during failover/restart when using multiple services #1703
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…g over with uncommitted pending service messages when running with multiple services.
…pending service messages.
mjpt777
approved these changes
Jan 6, 2025
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There is a bug in the Consensus Module where all service messages are appended to the same pending service message queue. The service container sends its service IDs as a session ID whereas the Consensus Module interprets it as a mask.
Where service messages are being sent from multiple services, these can be enqueued in different orders.
This means during failover/restart pending messages can be skipped or duplicated when a new leader is elected.
This change will affect users who are using cluster.offer() from multiple services.
Upgrade procedure
Those affected will need to do a clean shutdown (with a snapshot) and restart the whole cluster with the fix.
Is this upgrade procedure reasonable? How many people who haven't already worked around the duplicate/skipped message behaviour will be affected by this issue?