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This is the LHCb CERN LBD group page describing the local gateway machines

Local, batch, grid

What is it?

A gateway machine is a computer which is logged onto remotely, shared by multiple (limited) users.

What is it for?

The gateway machines are provided so that you can:

  • Maintain a session indefinately
  • Have a single machine name to remember
  • Run low-CPU consuming applications
  • Run mid-CPU consuming applications heavily 'niced'

Notably it is not for:

  • Do not run high-CPU consuming tasks, use the batch system or lhcbt3 for that.
  • Try not to rely on the temp directory, use your own personal scratch space or the group afs space for that, see CernLbdDiskSpace.


  • Submitting, monitoring and retrieving ganga jobs
  • Running small jobs against the nightlies
  • Compiling your code
  • Opening root files for viewing
  • running quick root macros


Use the CERN Terminal Services

Your cernts session will stay open for a very long time.

To check the service status and disconnect remotely see here


The LBD group with the fantastic help of the online team has provided a local SLC5 gateway machine, lbcsvr01 running a NX server. It is on the CERN network, afs-connected, and you will be able to keep a session open indefinitely.

Specs for lbcsvr01:

  • 12-core,
  • 24-GB-ram
  • 10GB network link,
  • stored in building 157
  • administrated with help from the online team, LoicBrarda and NikoNeufeld.

- Access:

  • If you are a member of LBD you are entitled to access the server
  • To gain access to the LBD server, contact RobLambert or NikoNeufeld, because your account needs to be added manually
  • You will be added to the lbcsrv-users e-group, and added individually to the machine
  • by requesting to join the lbcsrv-users e-group, Rob/Niko know you'd like to be added to the machine
  • Once you leave LBD, you will need to be removed from the list, and from the machine, but this will be done fairly, so don't panic... best to remember that it will happen, though

- Connecting through NX

NX will let you connect to the same desktop from multiple locations, and maintain that entire desktop as long as you wish.

NX is an improvement over VNC thanks to the simpler configuration, connection, and cut-pasting which was never 100% supported in VNC.

Over the CERN network:

  • Install the NX client on your machine from the website NX
  • clients can be Mac, Windows or Linux each of various flavours
  • Configure as you like, and run
  • choose the server, default port
  • Authenticate with your CERN username/password

From outside CERN.

  • not known yet

- Management

The administration of CERN lbd servers will be done on a fair-usage policy, if you are interfering with someone else, you will be asked to stop.

For management instructions see LBDGatewayManagement

- Known problems:

  1. afs freezing: probably needs update of open afs client as was done on lxplus
  2. kb broken in windows, only the number pad works, and none of the web clues fix the problem.


Emacs can't find fonts

  • emacs cannot find fonts
    ~ >emacs &
    >  Warning: Cannot convert string "-*-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-*" to type FontStruct
  • If you're on a windows machine you also need to install all the client font packs from the NX website.
  • (it's on the same page where you download the windows client)

Only the number pad works!

  • You can't seem to type anything, check the num pad, and it works
  • the keyboard mapping is wrong, probably
  • check what's in the server $HOME/.nx/C-<last-session>/options, if it says simply keyboard=pc105/en_US AND your local computer is not en_US then the local strings in your client are not set correctly.
  • follow the instructions here to fix it... but you'll need the client installed somewhere you have write permission!
  • if that doesn't help you, then probably the mapping is right in the client but there's something odd in the server, we're working on that.


See CernLbdPlatform.

-- RobLambert - 15-Nov-2010

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