nodetool drain
Flushes all memtables from the node to SSTables on disk.
HCD stops listening for connections from the client and other nodes.
Restart HCD after running nodetool drain.
Typically, use this command before upgrading a node to a new version of HCD.
To simply flush memtables to disk, use nodetool flush.
Synopsis
nodetool [<connection_options>] drainDefinition
If a parameter has multiple forms, the following reference provides both the short form and long form, separated by a comma.
Connection options
- -h, --host hostname
-
The hostname or IP address of a remote node or nodes. When omitted, the default is the local machine.
- -p, --port jmx_port
-
The JMX port number.
- -pw, --password jmxpassword
-
The JMX password for authenticating with secure JMX. If a password is not provided, you are prompted to enter one.
- -pwf, --password-file jmx_password_filepath
-
The filepath to the file that stores JMX authentication credentials.
- -u, --username jmx_username
-
The username for authenticating with secure JMX.
Command arguments
This command takes no arguments.
Examples
Flush memtables from node to SSTables on disk
nodetool drain