Common SSH issues

If you deleted the "@internal1" key from your profile

As long as you have at least one public key configured in your profile, use your SSH client to connect to gw.orbit-lab.org and run the following commands there. You do not need to make a reservation in the scheduler for this.

rm ~/.ssh/id_rsa
rm ~/.ssh/id_rsa.pub
ssh-keygen -t rsa -C "@internal1"

Press 'Enter' at every prompt so that the default filename (id_rsa) and no password is used.

Then type the following command:

cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys

The internal key should now be restored.

Common ssh options for nodes

We'd like to do a few things for convenience:

1. log into nodes as root by default
2. allow forwarding of X11 applications
3. Suppress annoying host key warnings

First, log into any console, or gw.orbit-lab.org

After logging in, create or modify the file at ~/.ssh/config

Add the following to the file

Host sdr?-md* sdr?-s?-lg* srv?-co* srv?-lg* node?-* node??-*
  User root
  UserKnownHostsFile /dev/null
  StrictHostKeyChecking no
  ForwardX11 yes

• Host: The Host line matches common naming conventions for nodes within the testbed
• User: root is set to match the common default for baseline
• UserKnownHostsFile: is set to /dev/null to prevent saving new host keys for nodes
• StrictHostKeyChecking: disables the warning message. SSH complains when host keys for a dns name change. This is a useful security feature, but is inconvenient within the testbed, where the operating system on a trusted machine changes frequently. Do not set it as a wildcard default for public endpoints, or you will be vulnerable to spoofing or man in the middle attacks.
• ForwardX11: allows the forwarding of graphical applications running the X11 protocol from a node back to your machine