Tarantella Administration Guide > Security > Tarantella and SSH

Tarantella and SSH

SSH (Secure SHell) is a package that lets you securely execute commands on network hosts. It offers a more secure alternative to the standard UNIX commands for this purpose (such as rsh and rlogin).

SSH provides the following benefits over the standard UNIX commands:

• All communication between hosts using SSH is encrypted -- including the X protocol if you're running X applications.
• Usernames and passwords are always encrypted before being transmitted over the network.

Tarantella can use SSH to provide secure communications between Tarantella servers and application servers. Tarantella works with SSH version 2.x or later.

Tarantella doesn't include SSH -- you'll need to obtain and install it separately. For more information see Installing and using SSH with Tarantella.

Enabling SSH with Tarantella

SSH is automatically detected when the Tarantella server starts, as long as SSH is installed in one of the following directories:

• /usr/local/bin
• /usr/bin
• /usr/sbin
• /usr/lbin
• /bin
• /sbin

If SSH is installed in a location not listed above or you want to use an SSH command-line argument:

1. Stop the Tarantella server:

   tarantella stop

2. Set the environment variable TTASSHCLIENT to the full pathname of the SSH program and any required command-line arguments, for example:

   TTASSHCLIENT="/usr/local/bin/ssh -q -X"; export TTASSHCLIENT

   Note If you just want to set command-line arguments, you have to include the pathname to the SSH program, even if the SSH program is in a location where Tarantella can detect it.

3. Edit the file /etc/services and add the following line:

   ssh 22/tcp

   Note This assumes you've configured the SSH daemon on the application server to use the default port (22/tcp).

4. Restart the Tarantella server:

   tarantella start