mirror of https://github.com/hashicorp/consul
65 lines
2.5 KiB
Markdown
65 lines
2.5 KiB
Markdown
---
|
|
layout: "docs"
|
|
page_title: "Commands: Exec"
|
|
sidebar_current: "docs-commands-exec"
|
|
description: |-
|
|
The exec command provides a mechanism for remote execution. For example, this can be used to run the `uptime` command across all machines providing the `web` service.
|
|
---
|
|
|
|
# Consul Exec
|
|
|
|
Command: `consul exec`
|
|
|
|
The `exec` command provides a mechanism for remote execution. For example,
|
|
this can be used to run the `uptime` command across all machines providing
|
|
the `web` service.
|
|
|
|
Remote execution works by specifying a job which is stored in the KV store.
|
|
Agent's are informed about the new job using the [event system](/docs/commands/event.html),
|
|
which propogates messages via the [gossip protocol](/docs/internals/gossip.html).
|
|
As a result, delivery is best-effort, and there is **no guarantee** of execution.
|
|
|
|
While events are purely gossip driven, remote execution relies on the KV store
|
|
as a message broker. As a result, the `exec` command will not be able to
|
|
properly function during a Consul outage.
|
|
|
|
## Usage
|
|
|
|
Usage: `consul exec [options] [-|command...]`
|
|
|
|
The only required option is a command to execute. This is either given
|
|
as trailing arguments, or by specifying '-', stdin will be read to
|
|
completion as a script to evaluate.
|
|
|
|
The list of available flags are:
|
|
|
|
* `-http-addr` - Address to the HTTP server of the agent you want to contact
|
|
to send this command. If this isn't specified, the command will contact
|
|
"127.0.0.1:8500" which is the default HTTP address of a Consul agent.
|
|
|
|
* `-datacenter` - Datacenter to query. Defaults to that of agent. In version
|
|
0.4, that is the only supported value.
|
|
|
|
* `-prefix` - Key prefix in the KV store to use for storing request data.
|
|
Defaults to "_rexec".
|
|
|
|
* `-node` - Regular expression to filter nodes which should evaluate the event.
|
|
|
|
* `-service` - Regular expression to filter to only nodes with matching services.
|
|
|
|
* `-tag` - Regular expression to filter to only nodes with a service that has
|
|
a matching tag. This must be used with `-service`. As an example, you may
|
|
do "-server mysql -tag slave".
|
|
|
|
* `-wait` - Specifies the period of time in which no agent's respond before considering
|
|
the job finished. This is basically the quiescent time required to assume completion.
|
|
This period is not a hard deadline, and the command will wait longer depending on
|
|
various heuristics.
|
|
|
|
* `-wait-repl` - Period to wait after writing the job specification for replication.
|
|
This is a heuristic value and enables agents to do a stale read of the job. Defaults
|
|
to 200msec.
|
|
|
|
* `-verbose` - Enables verbose output.
|
|
|