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---
layout: "docs"
page_title: "Commands: Exec"
sidebar_current: "docs-commands-exec"
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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.
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---
# Consul Exec
Command: `consul exec`
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The `exec` command provides a mechanism for remote execution. For example,
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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.
