Orchestrator GUI incorrectly shows recovery option for intermediate database in chained replication #1466
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intermediate database in chained replication openark#1463 Problem: If we've got replication chain A->B->C, and C is down, GUI shows 'Recover' dropdown for node B, but there is no possible recovery action available in such a case. Cause: The root cause of the problem is the analysis logic in Analysis_dao.go:GetReplicationAnalysis(). The condition for setting AllIntermediateMasterReplicasNotReplicating does not check if there are any replicas reachable. So the case when all replicas are dead (no recovery action possible) and the case when some replicas are still reachable, but are not replicating (recovery action possible) are undistingushable. Solution: Improve the analysis logic. Report AllIntermediateMasterReplicasNotReplicating only if all replicas are not replicating, but there are still some reachable replicas. This commit also contains improvement of not trying to query the node which is not reachable (ping node before examinig it)
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#1463
Problem:
If we've got replication chain A->B->C, and C is down, GUI shows 'Recover' dropdown for node B, but there is no possible recovery action available in such a case.
Cause:
The root cause of the problem is the analysis logic in Analysis_dao.go:GetReplicationAnalysis(). The condition for setting AllIntermediateMasterReplicasNotReplicating does not check if there are any replicas reachable. So the case when all replicas are dead (no recovery action possible) and the case when some replicas are still reachable, but are not replicating (recovery action possible) are undistingushable.
Solution:
Improve the analysis logic. Report
AllIntermediateMasterReplicasNotReplicating only if all replicas are not replicating, but there are still some reachable replicas.
This commit also contains improvement of not trying to query the node which is not reachable (ping node before examining it)