SSH Access

From Lsdf

Access to LSDF consoles and administrative interfaces is via SSH only. All administrative access is tunneled through a jumphost. Currently the jumphost is named

scc-cn-r164.scc.kit.edu

The jumphost has physical interfaces to the different consoles in the LSDF. Check with the admin of the jumphost to receive a login. He will ask you for your key (either private with password or public) that will be copied in your home directory of the 'jumphost'.

Common SSH problems

Most people have already access to different machines using SSH. Here are some things that may be less known but help if you have trouble accessing machines via ssh. Especially if you are on Windows this may help.

1) there are 2 different public (!) key file formats: OpenSSH and SSH2. Both formats use the same key encryption sequence and you could use an editor to convert one format to the other. Per default ssh-keygen on UNIX/Linux generates a SSH protocol 2 format public key.

2) As said above, the private key sequence is the same in both OpenSSH and SSH protocol 2. Its just the format that is different.

3) Your permissions must be set very strict. The .ssh directory (in your home) must have 700, the file with the private key must have 600. SSH refuses (silently) otherwise.

4) Windows users that use putty must be aware that putty has its own key format. Trying to read the OpenSSH key you have on Unix/Linux will fail. You have to import your private key using puttygen, then save the putty key. Alternatively you can create a key pair with puttygen. From the puttygen window you can copy the public key which then goes into the .ssh/authorized_keys dir on the remote host.