# `pcluster ssh`
<a name="pcluster.ssh"></a>

Runs an `ssh` command with the user name and IP address of the cluster pre-populated. Arbitrary arguments are appended to the end of the `ssh` command. This command can be customized in the aliases section of the configuration file.

```
pcluster ssh [ -h ] [ -d ] [ -r REGION ] cluster_name
```

## Positional arguments
<a name="pcluster.ssh.arg"></a>

***cluster\$1name***  
Specifies the name of the cluster to connect to.

## Named arguments
<a name="pcluster.ssh.namedarg"></a>

**-h, --help**  
Shows the help text for `pcluster ssh`.

**-d, --dryrun**  
Prints the command that would be run and exits.  
Defaults to `False`.

**-r *REGION*, --region *REGION***  
Specifies the AWS Region to use. Defaults to the Region specified by using the [`pcluster configure`](pcluster.configure.md) command.

**Examples using AWS ParallelCluster version 2.11.7:**

```
$ pcluster ssh -d mycluster -i ~/.ssh/id_rsa
SSH command: ssh ec2-user@1.1.1.1 -i /home/user/.ssh/id_rsa
```

```
$ pcluster ssh mycluster -i ~/.ssh/id_rsa
```

Runs `ssh` command with the user name and IP address of the cluster pre-populated:

```
ssh ec2-user@1.1.1.1 -i ~/.ssh/id_rsa
```

The `ssh` command is defined in the global configuration file under the [`[aliases]` section](aliases.md). It can be customized as follows.

```
[ aliases ]
ssh = ssh {CFN_USER}@{MASTER_IP} {ARGS}
```

Variables substituted:

`CFN_USER`  
The user name for the [`base_os`](cluster-definition.md#base-os) that is selected.

`MASTER_IP`  
The IP address of the head node.

`ARGS`  
Optional arguments to pass to the `ssh` command.