Login to ALICE from Linux

Login to ALICE from Linux

SSH Gateway and login nodes

The ssh gateway is named:

ssh-gw.alice.universiteitleiden.nl (132.229.92.63)

The login nodes are named:

login1.alice.universiteitleiden.nl (10.161.0.12)
login2.alice.universiteitleiden.nl (10.162.0.13)

Setup ssh JUMP

Here, we describe how you can configure your ssh connection to connect to ALICE in the easiest possible way. We will use a feature called ProxyJump in OpenSSH which is available in OpenSSH versions 7.3 and higher. If you have an older version of OpenSSH please have a look at SSH tunneling for older versions of OpenSSH. You can find out the version of OpenSSH by typing ssh -V in your terminal.

In your Linux system open ~/.ssh/config in your favourite text editor (or create the file if it does not exist). Then add for instance

Host hpc1 
  HostName login1.alice.universiteitleiden.nl
  User <USERNAME>
  ProxyJump <USERNAME>@ssh-gw.alice.universiteitleiden.nl:22
  
Host hpc2
  HostName login2.alice.universiteitleiden.nl
  User <USERNAME>
  ProxyJump <USERNAME>@ssh-gw.alice.universiteitleiden.nl:22

(Replace <USERNAME> by your own ULCN account name.)

Add monitoring tools

If you want to look at the monitoring tools that are running on the management node too, you could add additional tunnelling commands to the config for a specific host. Do not add tunnels to all definitions as they may produce conflicts when you use the same tunnel twice. So add the tunnel commands, for instance, to one host like:

Host hpc1tunnel
  HostName login1.alice.universiteitleiden.nl
  User <USERNAME>
  ProxyJump <USERNAME>@ssh-gw.alice.universiteitleiden.nl:22
  LocalForward 8081 management.alice.universiteitleiden.nl:8081
  LocalForward 8080 management.alice.universiteitleiden.nl:443

SSH tunneling for older versions of OpenSSH

Alternatively, if your OpenSSH server isn't that recent (version 7.2 or earlier) and doesn't recognize the ProxyJump alias, try this:

Host hpc1 
  HostName login1.alice.universiteitleiden.nl
  User <USERNAME>
  ProxyCommand ssh -X <USERNAME>@sshgw.alice.univesiteitleiden.nl -W %h:%p

Adding X11 fowarding

You can even set your ssh connection to automatic X11 forwarding by adding the following setting:

ForwardX11 yes

Direct login to login node 1

If you completed the above steps you should be able to login to one of the login nodes by simply typing this:

 ssh hpc1

Passwort-free login using SSH keys

Login to ssh-gw.alice.unversiteitleiden.nl (ssh <USERNAME>@ssh-gw.alice.universiteitleiden.nl and use your ULCN password for this) and put your public key in

~/.ssh/authorized_keys

Login through to the HPC login1 node ''ssh login1.alice.universiteitleiden.nl' (use your ALICE provided password) and put the same public key in

~/.ssh/authorized_keys

Accessing monitoring tools

Having set up the ssh tunneling required to access the monitoring tools on the cluster you are now able to access port 443 (general secure web server on the management node) and port 8081 (specific port in use by the Bright Cluster Manager monitoring tools).

So in a browser, you could type:

https://localhost:8080

to gain access to the management main web server, or you could type:

https://localhost:8081/userportal

to gain access to the Bright Cluster Manager User Portal.