» Command: node-drain

The node-drain command is used to toggle drain mode on a given node. Drain mode prevents any new tasks from being allocated to the node, and begins migrating all existing allocations away.

The node-status command compliments this nicely by providing the current drain status of a given node.

» Usage 

nomad node-drain [options] <node>

A -self flag can be used to drain the local node. If this is not supplied, a node ID or prefix must be provided. If there is an exact match, the drain mode will be adjusted for that node. Otherwise, a list of matching nodes and information will be displayed.

It is also required to pass one of -enable or -disable, depending on which operation is desired.

» General Options

  • -address=<addr>: The address of the Nomad server. Overrides the NOMAD_ADDR environment variable if set. Defaults to http://127.0.0.1:4646.

  • -region=<region>: The region of the Nomad server to forward commands to. Overrides the NOMAD_REGION environment variable if set. Defaults to the Agent's local region.

  • -no-color: Disables colored command output.

  • -ca-cert=<path>: Path to a PEM encoded CA cert file to use to verify the Nomad server SSL certificate. Overrides the NOMAD_CACERT environment variable if set.

  • -ca-path=<path>: Path to a directory of PEM encoded CA cert files to verify the Nomad server SSL certificate. If both -ca-cert and -ca-path are specified, -ca-cert is used. Overrides the NOMAD_CAPATH environment variable if set.

  • -client-cert=<path>: Path to a PEM encoded client certificate for TLS authentication to the Nomad server. Must also specify -client-key. Overrides the NOMAD_CLIENT_CERT environment variable if set.

  • -client-key=<path>: Path to an unencrypted PEM encoded private key matching the client certificate from -client-cert. Overrides the NOMAD_CLIENT_KEY environment variable if set.

  • -tls-skip-verify: Do not verify TLS certificate. This is highly not recommended. Verification will also be skipped if NOMAD_SKIP_VERIFY is set.

» Node Drain Options

  • -enable: Enable node drain mode.
  • -disable: Disable node drain mode.
  • -self: Drain the local node.
  • -yes: Automtic yes to prompts.

» Examples

Enable drain mode on node with ID prefix "4d2ba53b":

$ nomad node-drain -enable 4d2ba53b

Enable drain mode on the local node:

$ nomad node-drain -enable -self