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Advanced Support for TeraGrid Applications

SSH Version 1 and Version 2 compatibility

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If you want to get SSH2 working with SSH1 servers then these are the following steps you will need to take:

• Make and install the latest ssh-1.2.x (must be newer than 1.2.23).
• Make and install the newest ssh-2.x
  This will change the links in /usr/local/bin to point to the ssh2 version.
• Add (or change) the following lines in "/etc/ssh2/sshd2_config":

      Ssh1Compatability	yes
      Sshd1Path		/usr/local/sbin/sshd1
  

• Add (or change) the following lines in "/etc/ssh2/ssh2_config":

      Ssh1Compatability	yes
      Ssh1Path		/usr/local/bin/ssh1
  

Notes:
This will allow that machine to accept connections from both the 1.2.x and the 2.x clients. It will also allow you to connect to both the 1.2.x and 2.x servers (using bacwards compatability).

If the users want to remain using ssh1 (due to compatability) then you should change the /usr/local/bin links to point to the old ssh1 programs instead of the ssh2 variants (ssh-keygen2, ssh-agent2, ssh-add2, ssh2). They can then use 2 to work with ssh 2.x versions instead. Also note that the ssh-keygen2, ssh-agent2, and ssh-add2 programs are not compatible with ssh 1.2.x, so the 1 versions must be used instead.