Changes between Initial Version and Version 1 of User Guide/Remote Access/Ssh Tips

Timestamp:

May 19, 2020, 9:05:28 PM (5 years ago)

Author:

msherman

Comment:

—

User Guide/Remote Access/Ssh Tips

@@ +1 @@
+[[Include(WikiToC)]]
+==== SSH Tunneling
+
+A common need is to connect to some resource on the testbed as if it were local. SSH provides this functionality. Go to the [wiki:tutorials/ssh_tunnel Configuring SSH Tunnels tutorial] to learn how to configure these.
+  
+
+==== 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
+1. allow forwarding of X11 applications
+1. 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