Enabling Remote Execution with OpenSSH

To reduce the risk of network attacks and increase the security of your HP XC system, the traditional rsh, rlogin, and telnet tools are disabled by default, and OpenSSH is provided instead. HP XC systems use the OpenSSH package to provide a more secure environment than the traditional rsh, rlogin, and telnet tools. OpenSSH provides a secure, encrypted connection between your system and the HP XC system.

However, OpenSSH requires, by default, that users enter their password every time that they attempt to access a remote system. When first you use the ssh command to access the system, or when attempting to use a tool such as TotalView to debug an application on the cluster, you may be prompted to enter your password multiple times. To eliminate the multiple requests, use the procedure described below. Alternatively, you can use the ssh_create_shared_keys command, which is described in “Using the Secure Shell to Log In”

There are a number of ways in which to manage an OpenSSH environment. If you have not already established your own procedures, the following procedure will help you to get started. This procedure must be executed by each user, and assumes that your home directory is on a file system that is shared across the cluster.

Log in to your account on the system and execute the following commands. Press the ENTER key in response to all questions.

$ ssh-keygen -t dsa
$ cd ~/.ssh
$ cat id_dsa.pub >>authorized_keys
$ chmod go-rwx authorized_keys