Command: job action
Alias: nomad action
The job action
command allows operators to execute predefined actions declared
in Nomad job specifications. These actions can be defined at task level and are
intended for specific operational tasks, such as clearing a cache, or migrating
a database.
An action may self-terminate upon completion (for example, echoing a string), or run for an indeterminate amount of time (for example, watching a blocking query). In the latter case, an action can be terminated via escape character (such as cmd+c / ctrl+c)
When ACLs are enabled, this command requires a token with the alloc-exec
,
read-job
, and list-jobs
capabilities for the allocation's namespace. If
the task driver does not have file system isolation (as with raw_exec
),
this command requires the alloc-node-exec
, alloc-exec
, read-job
, and
list-jobs
capabilities for the allocation's namespace.
Usage
The job action
command requires an action name and accepts two ways of
specifying where it should run:
- by passing the job name and known allocation ID along with the name of the action
- by passing the job, task group, and task name along with the name of the action (when the allocation ID is not known). A random allocation will be selected if multiple are available.
The action name provided must be defined within a task in the job specification provided. With sufficient privileges, an execution context will be opened and the defined action command will be run. No further input is possible, save for the escape character to terminate execution, so interactive commands are not supported.
General Options
-address=<addr>
: The address of the Nomad server. Overrides theNOMAD_ADDR
environment variable if set. Defaults tohttp://127.0.0.1:4646
.-region=<region>
: The region of the Nomad server to forward commands to. Overrides theNOMAD_REGION
environment variable if set. Defaults to the Agent's local region.-namespace=<namespace>
: The target namespace for queries and actions bound to a namespace. Overrides theNOMAD_NAMESPACE
environment variable if set. If set to'*'
, subcommands which support this functionality query all namespaces authorized to user. Defaults to the "default" namespace.-no-color
: Disables colored command output. Alternatively,NOMAD_CLI_NO_COLOR
may be set. This option takes precedence over-force-color
.-force-color
: Forces colored command output. This can be used in cases where the usual terminal detection fails. Alternatively,NOMAD_CLI_FORCE_COLOR
may be set. This option has no effect if-no-color
is also used.-ca-cert=<path>
: Path to a PEM encoded CA cert file to use to verify the Nomad server SSL certificate. Overrides theNOMAD_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 theNOMAD_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 theNOMAD_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 theNOMAD_CLIENT_KEY
environment variable if set.-tls-server-name=<value>
: The server name to use as the SNI host when connecting via TLS. Overrides theNOMAD_TLS_SERVER_NAME
environment variable if set.-tls-skip-verify
: Do not verify TLS certificate. This is highly not recommended. Verification will also be skipped ifNOMAD_SKIP_VERIFY
is set.-token
: The SecretID of an ACL token to use to authenticate API requests with. Overrides theNOMAD_TOKEN
environment variable if set.
Action Options
-job
: (Required) Specifies the job containing the predefined action.-alloc
: Specifies the allocation within which the action is to be executed. If omitted,-group
and-task
must be provided, and a random allocation for the group will be selected.-task
: Specifies the task within the job where the action is defined. This is required either if-alloc
provided and your group has multiple tasks, or if you specify a-group
.-group
: Specifies the task group within the job. If present, a random allocation is selected. If omitted,-alloc
must be provided.-i
: Pass stdin to the action, defaults totrue
. Pass-i=false
to disable explicitly.-t
: Allocate a pseudo-tty, defaults totrue
if stdin is detected to be a tty session. Pass-t=false
to disable explicitly.-e
<escape_char>: Sets the escape character for sessions with a pty, defaults to '~'. The escape character is only recognized at the beginning of a line. The escape character followed by a dot (.
) closes the connection. Setting the character tonone
disables any escapes and makes the session fully transparent.
Examples
Execute an action within a specific task in a job:
Execute an action within a specific allocation: