raft: Set the RecentActive flag for newly added nodes#7830
Merged
xiang90 merged 2 commits intoetcd-io:masterfrom May 5, 2017
Merged
raft: Set the RecentActive flag for newly added nodes#7830xiang90 merged 2 commits intoetcd-io:masterfrom
xiang90 merged 2 commits intoetcd-io:masterfrom
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I found that enabling the CheckQuorum flag led to spurious leader elections when new nodes joined. It looks like in the time between a new node joining the cluster, and that node first communicating with the leader, the quorum check could fail because the new node looks inactive. To solve this, set the RecentActive flag when nodes are first added. This gives a grace period for the node to communicate before it causes the quorum check to fail. Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
Author
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Any thoughts on this propsed change? The extra leader elections when |
Contributor
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can you write a test for this? |
Contributor
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this change looks reasonable. |
This test verifies that adding a node does not cause the leader to step down until at least one full ElectionTick cycle elapses. Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
Author
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Thanks. I've added a test. |
Contributor
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LGTM. |
Contributor
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@aaronlehmann Thanks. |
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I found that enabling the
CheckQuorumflag led to spurious leader elections when new nodes joined. It looks like in the time between a new node joining the cluster, and that node first communicating with the leader, the quorum check could fail because the new node looks inactive. To solve this, set theRecentActiveflag when nodes are first added. This gives a grace period for the node to communicate before it causes the quorum check to fail.This seems like a decent way to solve the problem, but please feel free to suggest other approaches instead.