Removing the fileserver role from a node is more complex than removing other roles. The CLDB tracks data precisely on all fileserver nodes, and therefore you should direct the cluster CLDB to stop tracking the node before removing the fileserver role.

For a planned decommissioning of a node, use node topologies to migrate data off the node before removing the fileserver role. For example, you could move the node out of a live /data topology into a /decommissioned topology that has no volumes assigned to it, in order to force data off the node. Otherwise, some data will be under-replicated as soon as the node is removed. Refer to Node Topology.

The following procedure involves halting all MapR services on the node temporarily. If this will disrupt critical services on your cluster, such as CLDB or JobTracker, migrate those services to a different node first, and then proceed.

To Remove the fileserver role from a node

  1. Stop the warden, which will halt all MapR services on the node.
  2. Wait 5 minutes, after which the CLDB will mark the node as critical.
  3. Remove the node from the cluster, to direct the CLDB to stop tracking this node. You can do this in the MapR Control System GUI or with the maprcli node remove command.
  4. Remove the fileserver role by deleting the file /opt/mapr/roles/fileserver on the node.
  5. Run configure.sh on the node to reconfigure the node without the fileserver role.
  6. Start the warden.
  7. Remove any volumes that were stored locally on the node. You can do this in the MapR Control System GUI or with the maprcli volume remove command.

For example:

/opt/mapr # service mapr-warden stop
     ...wait 5 minutes for CLDB to recognize the node is down...
/opt/mapr # maprcli node remove 10.10.80.61
/opt/mapr # rm /opt/mapr/roles/fileserver
/opt/mapr # /opt/mapr/server/configure.sh -R
/opt/mapr # service mapr-warden start
/opt/mapr # maprcli volume remove -name mapr.mapr-desktop.local.logs
/opt/mapr # maprcli volume remove -name mapr.mapr-desktop.local.mapred
/opt/mapr # maprcli volume remove -name mapr.mapr-desktop.local.metrics