cluster show health v5.6

Checks the health of the EDB Postgres Distributed cluster

Synopsis

Performs various checks such as if all nodes are accessible and all replication slots are working.

Please note that the current implementation of clock skew may return an inaccurate skew value if the cluster is under high load while running this command or has large number of nodes in it.

pgd cluster show health [flags]

Examples

With a node down

In this example, a 3 node cluster has two nodes up, bdr-a1 and bdr-c1, but one node, bdr-b1, down.

$ pgd cluster show health
Output
Check      Status   Message
-----      ------   -------
ClockSkew  Critical Clockskew cannot be determined for at least 1 BDR node pair
Connection Critical The node bdr-b1 is not accessible
Raft       Warning  There is at least 1 node that is not accessible
Replslots  Critical There is at least 1 BDR replication slot which is inactive
Version    Warning  There is at least 1 node that is not accessible

With unsynchronized system clocks

In this example, a 3 node cluster has all nodes are up but the system clocks aren't in synchronized.

$ pgd cluster show health
Output
Check      Status  Message
-----      ------  -------
ClockSkew  Warning At least 1 BDR node pair has clockskew greater than 2 seconds
Connection Ok      All BDR nodes are accessible
Raft       Ok      Raft Consensus is working correctly
Replslots  Ok      All BDR replication slots are working correctly
Version    Ok      All nodes are running same BDR versions

Cluster functioning correctly

In this example, a 3 node cluster has all nodes are up and the system clocks are in synchronized.

$ pgd cluster show health
Output
Check      Status Message
-----      ------ -------
ClockSkew  Ok     All BDR node pairs have clockskew within permissible limit
Connection Ok     All BDR nodes are accessible
Raft       Ok     Raft Consensus is working correctly
Replslots  Ok     All BDR replication slots are working correctly
Version    Ok     All nodes are running same BDR versions