Reduce the size of a data center.
Use these instructions when you want to remove up nodes to reduce the size of your
cluster, not for replacing a dead node. Attention: If you are not using
virtual nodes (vnodes),
you must rebalance the cluster.
Procedure
-
Check whether the node is up or down using nodetool status:
The nodetool command shows the status of the node:
-
If the node is up, run nodetool
decommission.
This assigns the ranges that the node was responsible for to other nodes and
replicates the data appropriately.
Use nodetool netstats to monitor
the progress.
-
If the node is down:
- If the cluster uses vnodes, remove the node using the nodetool removenode
command.
- If the cluster does not use vnodes, before running the nodetool removenode
command, adjust your tokens to evenly distribute the data across the
remaining nodes to avoid creating a hot spot. See the following in the
Cassandra 1.1 documentation: