TransportResyncReplicationAction should not honour blocks #35795
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tlrx added >enhancement v7.0.0 :Distributed Indexing/Distributed 
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| Pinging @elastic/es-distributed |
ywelsch approved these changes Nov 21, 2018
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| @Override | ||
| protected ClusterBlockLevel globalBlockLevel() { | ||
| // resync should never be blocked |
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maybe add here "because it's an internal action"
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| Thanks @ywelsch |
tlrx added a commit that referenced this pull request Nov 22, 2018
After #35332 has been merged, we noticed some test failures like #35597 in which one or more replica shards failed to be promoted as primaries because the primary replica re-synchronization never succeed. After some digging it appeared that the execution of the resync action was blocked because of the presence of a global cluster block in the cluster state (in this case, the "no master" block), making the resync action to fail when executed on the primary. Until #35332 such failures never happened because the TransportResyncReplicationAction is skipping the reroute phase, the only place where blocks were checked. Now with #35332 blocks are checked during reroute and also during the execution of the transport replication action on the primary. After some internal discussion, we decided that the TransportResyncReplicationAction should never be blocked. This action is part of the replica to primary promotion and makes sure that replicas are in sync and should not be blocked when the cluster state has no master or when the index is read only. This commit changes the TransportResyncReplicationAction to make obvious that it does not honor blocks. It also adds a simple test that fails if the resync action is blocked during the primary action execution. Closes #35597
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After #35332 has been merged, we noticed some test failures like #35597 in which one or more replica shards failed to be promoted as primaries because the primary replica re-synchronization never succeed.
After some digging it appeared that the execution of the resync action was blocked because of the presence of a global cluster block in the cluster state (in this case, the "no master" block), making the resync action to fail when executed on the primary.
Until #35332 such failures never happened because the
TransportResyncReplicationActionis skipping the reroute phase, the only place where blocks were checked. Now with #35332 blocks are checked during reroute and also during the execution of the transport replication action on the primary. After some internal discussion, we decided that theTransportResyncReplicationActionshould never be blocked. This action is part of the replica to primary promotion and makes sure that replicas are in sync and should not be blocked when the cluster state has no master or when the index is read only.This pull request changes the
TransportResyncReplicationActionto make obvious that it does not honor blocks. It also adds a simple test that fails if the resync action is blocked during the primary action execution.Closes #35597