mirror of https://github.com/ceph/ceph
31 lines
1.1 KiB
ReStructuredText
31 lines
1.1 KiB
ReStructuredText
==================================
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Recovering from Monitor Failures
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==================================
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In production clusters, we recommend running the cluster with a minimum
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of three monitors. The failure of a single monitor should not take down
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the entire monitor cluster, provided a majority of the monitors remain
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available. If the majority of nodes are available, the remaining nodes
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will be able to form a quorum.
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When you check your cluster's health, you may notice that a monitor
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has failed. For example::
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ceph health
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HEALTH_WARN 1 mons down, quorum 0,2
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For additional detail, you may check the cluster status::
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ceph status
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HEALTH_WARN 1 mons down, quorum 0,2
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mon.b (rank 1) addr 192.168.106.220:6790/0 is down (out of quorum)
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In most cases, you can simply restart the affected node.
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For example::
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service ceph -a restart {failed-mon}
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If there are not enough monitors to form a quorum, the ``ceph``
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command will block trying to reach the cluster. In this situation,
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you need to get enough ``ceph-mon`` daemons running to form a quorum
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before doing anything else with the cluster. |