Ozone Manager Leader Transfer

The ozone admin om transfer command allows you to manually transfer the leadership of the Ozone Manager (OM) Raft group to a specific OM node or to a randomly chosen follower.

Until HDDS-17124 is fixed, manual OM and SCM leadership transfer commands have taken approximately 4–13 seconds in five-node tests because of Ratis client retry waits during leader discovery and priority reset. This is an observation, not an upper bound or a guarantee about automatic failover latency. Account for client RPC timeouts; if a command times out, check the current roles before deciding whether to retry.

Usage

ozone admin om transfer -id <OM_SERVICE_ID> -n <NEW_LEADER_ID>
ozone admin om transfer -id <OM_SERVICE_ID> -r

• -id, --service-id: Specifies the Ozone Manager Service ID.
• -n, --newLeaderId, --new-leader-id: The node ID of the OM to which leadership will be transferred (e.g., om1).
• -r, --random: Randomly chooses a follower to transfer leadership to.

Example

To transfer leadership to om2 in a cluster with service ID cluster1:

ozone admin om transfer -id cluster1 -n om2

To transfer leadership to a random follower:

ozone admin om transfer -id cluster1 -r