Configuring a Secure Shell environment for IBM Streams

In previous releases, IBM® Streams used Secure Shell (SSH) to run product applications, commands, and scripts. Beginning in Version 4.0, using SSH is optional. If you are using SSH, you must configure a Secure Shell environment for IBM Streams before you use the product.

1. Set up your SSH keys.
   1. Enter ssh-keygen -t dsa.
   2. When prompted, enter a key file name or press Enter to accept the default name. See  1  in the sample command output.
   3. When prompted for a passphrase, press Enter twice without entering the passphrase. See  2  and  3  in the sample command output.
   The following example shows the ssh-keygen command output:

   [bsmith@server44 ~]$ ssh-keygen -t dsa
   Generating public/private dsa key pair.
   Enter file in which to save the key (/home/bsmith/.ssh/id_dsa):  1 
   Created directory '/home/bsmith/.ssh'.
   Enter passphrase (empty for no passphrase):  2 
   Enter same passphrase again:  3 
   Your identification has been saved in /home/bsmith/.ssh/id_dsa.
   Your public key has been saved in /home/bsmith/.ssh/id_dsa.pub.
   The key fingerprint is:
   6e:72:23:80:55:ec:73:d1:7f:10:09:16:a7:71:61:0d bsmith@server44.ibm.com

   The ssh-keygen command creates an .ssh directory (home-directory/.ssh), if it does not exist, and two key files (id_dsa.pub for the public key and id_dsa for the private key).
2. Switch to the .ssh directory by typing the following command:

     cd ~/.ssh

3. Append the public key file to the authorized_keys file by typing the following command:

     cat id_dsa.pub >> authorized_keys

4. SSH requires that only the owner has access to the key files. Change the permission on the files in the .ssh directory by typing the following command:

     chmod 600 *

   SSH also requires that only the owner has write access to the .ssh directory. The ssh-keygen command creates this directory with the appropriate mode.
5. SSH requires that only the owner has write access to their home directory. To satisfy this requirement, type the following command:

    chmod go-w ~

6. Test your SSH settings by using the streamtool checkhosts command.