5.7. Monitoring Replication Parameters

When you configure replication parameters, keep in mind that the new settings do not come into effect immediately. For example, increasing the default replication parameter for data chunks may take some time to complete, depending on the new value of this parameter and the number of data chunks in the cluster.

To check that the new replication parameters have been successfully applied to your cluster:

  1. Run the vstorage -c <cluster_name> top command.

  2. Press V to display additional information about the cluster. Typical command output may look like this:

    # vstorage -c stor1 top
    Cluster 'stor1': healthy
    Space: [OK] allocatable 448.6GB of 492.0GB, free 1.39TB of 1.44TB
    MDS nodes: 3 of 3, epoch uptime: 20d  0h
    CS nodes:  3 of 3 (3 avail, 0 inactive, 0 offline)
    License: ACTIVE (expiration: 01/10/2021, capacity: 10TB, used: 20.3GB)
    Replication:  3 norm,  2 limit
    Chunks: [Warning] 187 (57%) healthy,  0 (0%) standby,  0 (0%) degraded,  135 (41%) urgent,
                 0 (0%) blocked,  0 (0%) pending,  0 (0%) offline,  1 (0%) replicating,
                 0 (0%) overcommitted,  0 (0%) deleting,  0 (0%) void
    IO:       read     0B/s (  0ops/s), write  106KB/s (  7ops/s)
    ...
    
  3. Check the Chunks field for the following:

    • When decreasing the replication parameters, look for chunks that are in the overcommitted or deleting state. If the replication process is complete, no chunks with these states should be present in the output.
    • When increasing the replication parameters, look for chunks that are in the blocked or urgent state. If the replication process is complete, no chunks with these states should be present in the output. Besides, when the process is still in progress, the value of the healthy parameter is less than 100%.

    For more information on available chunk statuses, see Exploring Chunk States.