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  1. Couchbase Kubernetes
  2. K8S-493

Need a way to map ONLY logs to a persistent volume

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Details

    • Improvement
    • Status: Resolved
    • Blocker
    • Resolution: Fixed
    • None
    • 1.1.0
    • operator

    Description

      From our discussions at the Supportability Design meeting, we agreed that we would not be able to solve the problem of collecting logs from Couchbase Server pods which have been deleted by the operator in the 1.0 timeframe.
      A compromise was made to instead make it easy for users to setup persistent volumes for logs so that at least these get re-attached to incoming replacement pods. Alternatively, they can attach the persistent volume to their own pods to access the logs if needed.
      While this does not solve the problem entirely, it is a very acceptable solution for most cases.
      It was my understanding at the time of that meeting that it would be easy to map specific mount points (e.g. /opt/couchbase/var/lib/couchbase/logs) to persistent volumes.

      From reviewing the documentation for persistent volumes it appears that is impossible to setup PVCs for logs (reference: https://github.com/couchbase/couchbase-operator/blob/master/docs/user/modules/ROOT/pages/couchbase-cluster-config.adoc#specserverspodvolumemounts).
      It is possible to setup a ‘default’ volume mount, which mounts the entirety of /opt/couchbase/var/lib/couchbase, but this is not really acceptable to most users who require high performance from their disks (i.e. won’t want to use PVs for data or indexes). These users will instead want their data mounted on the local ephemeral storage, which is their only option for local storage before host storage becomes a persistent volume option within Kubernetes.

      You could argue that we’re trying to solve a problem that won’t exist when host storage becomes GA within Kubernetes, but we do not know exactly when that will be.

      I do not know the exact level of work required to add in a way of mapping ONLY the logs directory to a persistent volume, but I feel we have to get this added to 1.0 of the operator if at all possible.

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        Activity

          matt.carabine Matt Carabine created issue -
          tommie Tommie McAfee made changes -
          Field Original Value New Value
          Assignee Mike Wiederhold [ mikew ] Tommie McAfee [ tommie ]
          mikew Mike Wiederhold [X] (Inactive) made changes -
          Fix Version/s 1.1.0 [ 15163 ]
          mikew Mike Wiederhold [X] (Inactive) made changes -
          Rank Ranked higher
          lynn.straus Lynn Straus made changes -
          Labels releasenote
          anil Anil Kumar made changes -
          Priority Blocker [ 1 ] Critical [ 2 ]
          mikew Mike Wiederhold [X] (Inactive) made changes -
          Rank Ranked higher
          mikew Mike Wiederhold [X] (Inactive) made changes -
          Rank Ranked higher
          mikew Mike Wiederhold [X] (Inactive) made changes -
          Priority Critical [ 2 ] Blocker [ 1 ]
          mikew Mike Wiederhold [X] (Inactive) made changes -
          Resolution Fixed [ 1 ]
          Status Open [ 1 ] Resolved [ 5 ]

          People

            tommie Tommie McAfee
            matt.carabine Matt Carabine
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            Dates

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              Updated:
              Resolved:

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