Login servers

This article explains:

• Available login servers 
• Features of login servers
• Contingency route for users with network difficulties 
• How to use the login servers to access resources within JASMIN

Available login servers 

There are three login servers available to access resources within JASMIN. Users with the  jasmin-login access role can access the following servers via SSH:

If you require more detailed instructions on how to log in from different types of computer refer to the getting started category

See also NoMachine NX service which provides login to a graphical Linux desktop, rather than a single terminal window.

Features of login servers

Login servers have minimal resources and software installed.  They provide:

• Access to your home directory (/home/users/<username>).
• Access over SSH to other hosts within JASMIN (inside the RAL firewall)
• No analysis software is installed on the login servers.
• No access to group workspaces or other volumes.

"Contingency" login servers

There are requirements on your local network which apply to accessing the login servers and the transfer servers via SSH. If you cannot meet these requirements, even after discussion with your local network admin team, a contingency route is provided in the form of login server login2.jasmin.ac.uk 

However, you will be limited in what you can access within JASMIN from this server. Specifically:

• You will not be able to access the transfer servers xfer[1,2].jasmin.ac.uk  via SSH directly from an external host.
  
  • You can access these using a "hop" from login2, but can then only initiate an inward pull of data from an external SSH server, if available at your institution. You cannot push data directly to xfer[1,2].jasmin.ac.uk via SSH from outside in this case.
  • Instead, an alternative transfer server xfer3.jasmin.ac.uk is provided with equivalent configuration to login2. This should provide what you need for direct SSH transfers from outside, but you will need the additional "xfer-sp" access role in in this case: see here for further details.
• You cannot set up SSH tunnelling to other hosts within JASMIN.

How to use the login servers

For full details of how to log in, including making onward connections to other machines, please see the article "How to login"

Note: Users are not permitted to execute commands which require administrative privileges. This applies to all hosts in the managed part of JASMIN where users have SSH login access (for example login, nx-login, sci, xfer and hpxfer machines). In other words, the use of  su or sudo is not permitted. Please be careful when typing commands, particularly if you have multiple terminal windows open on your own computer, that you do not accidentally attempt sudoon a JASMIN machine: expect some follow-up from the JASMIN team if you do!