2024-01-08 11:28:31 +00:00
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---
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layout: page
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title: Failover Leader service
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parent: List of all features
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---
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2023-06-26 10:35:56 +00:00
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# Failover Leader service
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## Overview
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This feature is designed to solve the problem with the Leader service in Active Failover mode.
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It attaches the `deployment.arangodb.com/leader=true` label to the Leader member of the cluster.
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If a member is a Follower, then this label is removed.
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Above labels are used by the cluster Services to route the traffic to the Leader member.
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In case of double Leader situation (which will be fixed in future versions of ArangoDB),
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the operator will remove the `deployment.arangodb.com/leader=true` label from all members,
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which will cause the cluster outage.
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## How to use
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This feature is disabled by default.
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To enable it use `--deployment.feature.failover-leadership ` arg, which needs be passed to the operator:
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```shell
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helm upgrade --install kube-arangodb \
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https://github.com/arangodb/kube-arangodb/releases/download/$VER/kube-arangodb-$VER.tgz \
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--set "operator.args={--deployment.feature.force-rebuild-out-synced-shards}"
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```
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