partition_balancer: report quorum loss moves as...#28393
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immutable nodes_decommissioning_test.py ::NodesDecommissioningTest .test_decommissioning_node_rf_1_replica would periodically fail on partitions not being reported as allocation failures. This happened because there was a race. A partition would NOT be reported as an allocation failure if there was a move in progress. In this test, the node is stopped and then the decommed. As a result, the broker could be picked up as unresponsive, which would init a move before the decomission is made visible to the planner. This commit changes pbp to report in-progress moves with quorum loss on the original replica set as immutable.
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/ci-repeat 1 |
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CI test resultstest results on build#75724
test results on build#75764
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joe-redpanda
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bashtanov,
bharathv,
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mmaslankaprv
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Pull Request Overview
This PR fixes a race condition in the partition balancer planner where partitions that have lost quorum during an in-progress move were not being reported as allocation failures. The fix ensures that partitions with an in-flight move and quorum loss on the original replica set are now correctly reported as immutable.
Key Changes:
- Added quorum loss detection for partitions during in-progress moves
- Partitions that lost quorum during moves are now reported as immutable with
no_quorumreason - Restructured control flow to handle the new quorum loss case before attempting cancellations
mmaslankaprv
approved these changes
Nov 21, 2025
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/backport v25.3.x |
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/backport v25.2.x |
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/backport v25.1.x |
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/backport v24.3.x |
This was referenced Nov 21, 2025
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...immutable
nodes_decommissioning_test.py
::NodesDecommissioningTest
.test_decommissioning_node_rf_1_replica
would periodically fail on partitions not being reported as allocation failures. This happened because there was a race. A partition would NOT be reported as an allocation failure if there was a move in progress.
In this test, the node is stopped and then the decommed. As a result, the broker could be picked up as unresponsive, which would init a move before the decomission is made visible to the planner.
This commit changes pbp to report in-progress moves with quorum loss on the original replica set as immutable.
Backports Required
Release Notes
Improvements