Known Remote Access Issues

FAQ Remote Access

 I can't log in

There can be several reasons for this:

  1. You aren't registered on a visit on a beamline at this time
  2. You are trying to connect to the wrong beamline
  3. You are over quota in your home directory
  4. You've added something to your .bashrc or .bashrc_local
  5. The ssh key has changed
  6. You are using the wrong FedID or password


  1. You aren't registered on a visit on a beamline at this time
  2. If you aren't registered on a visit you cannot log in to a beamline. Outside of working hours this is likely unfixable in the time frame you require - you should have registered for the visit well ahead of the scheduled beamtime in the user administration system. During working hours please contact your BAG PI to register you in the system.

  3. You are trying to correct to the wrong beamline
  4. You only have permission to connect to the beamline your visit is scheduled on. To check which beamline you are registered on please check your emails from the User Office or log in to UAS or ISPyB and check the calendars.

  5. You are over quota in your home directory
  6. If you can't connect either to the beamline using the nxclient then you may be over quota.

    Linux/ Mac

    To test this firstly ssh to (i.e. at a terminal type ssh and login with your password - if you can't login via ssh to please proceed to point 4 and then point 5), check your quota (type quota on the command line). If you are over quota you will need to delete some files. Usual culprits are mozilla or processed data in your home directory. To check the size of files and directories type du -hs * to find the main culprits for deletion. Once you've deleted files and you are under quota you should be able to log-in to the beamline.


    Install a tool such as putty to allow ssh connections, then follow instructions for Linux/Mac in the putty terminal.


  7. You've added something ot your .bashrc or .bashrc_local
  8. If you have added "module load mx" and/or "module load python/anaconda" to either .bashrc or .bashrc_local in your home directory you may not be able to log in via nx.

    Linux/ Mac

    To remove this ssh -X and use a command line editor to remove these lines from these files.


    Install a tool such as putty to allow ssh connections, then follow instructions for Linux/Mac in the putty terminal.

  9. The ssh key has changed
  10. Periodically (typically during shutdowns) our linux systems are reinstalled and keys for ssh are updated which result in mismatch in ssh keys in your local account .ssh/known_hosts file. If you are getting the following message (or similair): "Permission denied (publickey,gssapi-keyex,gssapi-with-mic,password)".

    Linux/ mac os

    In the home directory on your local machine type cd .ssh and delete the file known_host using the command rm  known_hosts. Please try to log in again and follow the on screen commands. If this doesn't succeed please proceed to point 5.


    You should be prompted to alter the ssh keys by no machine. If not these are stored under your home directory, in a .ssh folder. You will need to show hidden files to see this folder. Then remove either open the file and remove any hosts associated with diamond, or remvoe the whole file. 

  11. You are using the wrong FedID or password
  12. You may be inadvertently using the wrong FedID or password. You can check your FedID and register with the STFC password manager to reset your password here. We recommend you do this immediately if you fail to log in twice. Following a third failed attempt with either incorrect FedID or password further log in attempts from your IP will be temporarily blocked for 15 minutes. If you are on a private network behind a firewall the Diamond systems will only see the IP address at your gateway - consequently this means if you or your colleagues make three failed attempts from any machine with any FedID from behind this gateway machine further attempts from inside this will be also be temporarily blocked since we only see your gateway IP. Please wait for this temporary block to end.

Various issues:

GDA doesn't start

You may not have a registered visit today. GDA only starts when you have a visist scheduled. If you wish to test remote access prior to an experiment please contact to set up a test session during a machine day or shutdown. If you are trying to process data check our video.

In NX player for Mac, where is the '#' symbol?

The keyboard shortcut for '#' symbol is 'alt (to the right of the space bar)' + '3'

How to expand NX remote session on 2 screens?

 In nomachine options (top right corner) choose "Display" and "Fullscreen on all screens"



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