Remote Access to Linux Systems

There are several ways you can remotely access the departmental Linux systems (which include various compute systems and desktops).

Remote Access Portal

The easiest way to get a full remote Linux session (on one of the departmental compute systems) is to use the remote access portal (RAP). Using a web browser:

  • Resize the browser window to the desktop size you would like for your remote session. [Any resizing of the browser window done after connection will only rescale what you see and not provide more remote desktop area]
  • Visit the remote access portal https://rap.maths.ox.ac.uk
  • Login with your usual departmental IT account details
  • Select the machine you wish to connect to from the list that appears
  • In the session login window that appears, login with your usual departmental IT account details

A full graphical session (as you would get on a Linux desktop etc) will now appear within the browser window.

When finished remember to use the session logout button to end the session and then close the browser/browser tab.

If you do not logout of the remote session and simply close the browser window, then the session will continue to run on the server and you can reconnect to it when desired simply by revisiting RAP and choosing the same machine.

Sometimes you may find a password you are confident is correct is not working at the Linux or Windows session login. If that happens then there are several things you can try/check:

  • make sure you are entering your username in lowercase only!
  • use SHIFT not CAPS-LOCK where needed in the password as some people have experienced problems with CAPS-LOCK failing to be transmitted and thus the password failing to be entered correctly
  • type more slowly as some people have found keypresses are missed or mixed up when typed quickly
  • think about characters that may be in a different place on a US keyboard as some people find the login screen defaults to a US key layout

X2Go

X2Go is an implementation of the NX protocol (which we formerly used with FreeNX and nxclient).

Note if you use this to remotely connect to a departmental desktop then you may need to wake the desktop first.

Client installation

To use X2Go you firstly need to install the x2goclient (this is installed by default on departmental desktops and laptops) for your particular operating system.

Client configuration

Having installed the client you need to first configure it:

X2Go Session Configuration

  • Start the x2goclient
  • Select Session -> New Session
  • In the dialog that appears set:
    • Session name: e.g. Connection to Maths
    • Host: name of the machines machine you will connect to, e.g. perkin.maths.ox.ac.uk
    • Login: your maths IT account user name
    • Session type: MATE (we switched from GNOME in Dec 2020)
  • In the Settings tab you may want to define a custom display size (i.e. how big the window should be for the desktop session)
  • If you are not connecting from a machine on the maths network (either the departmental desktops or the MATHS wifi), then also enter ssh proxy settings:
    • Use proxy server for ssh connection: tick this box to reveal further settings
    • Same login as on X2Go Server: tick this box
    • Same password as on X2Go Server: tick this box
    • Host: gate.maths.ox.ac.uk
  • Now click ok to save these session settings

You can now use this defined session to start a connection. It may ask you to accept the ssh key fingerprint for gate.

If when you connect to a MATE session the windows and fonts are larger than expected then you can adjust this as follows. Click on the button at the very top right of the screen, and select 'system settings'. Click on the 'Appearance' settings and in the window that appears go into the Fonts tab. Click on the 'Details' button near the bottom, and in the new window that appears turn off automatic detection and set the dots per inch to 96.

If you connect to a MATE session you see a thick black border around each window then you can resolve this as follows. Click on the button at the very top right of the screen, and select 'system settings'. Click on the 'Windows' settings and in the window that appears untick the option 'enable software compositing window manager'.

When finished remember to use the session logout button to end the session.

If you do not logout of the remote session and simply close the x2go window, then the session will continue to run on the server and you can reconnect to it when desired simply by using the same session starter within the x2go client.

Text only session

If you just want a text terminal session you can connect via ssh to the machine gate.maths.ox.ac.uk (see the ssh key fingerprints page as it may prompt to accept the key). Note gate is intended as a gateway into the system and does not have much local software. You may thus wish to ssh from there to a particular compute or desktop machine. You can combine this with GNU screen to allow you to disconnect and reconnect to a running text session.