Contents

  1. General Login
  2. Login from LXPLUS
  3. Login from your laptop
  4. Dedicated GRID Proxy for the NAF

General Login

Follow the instructions on http://naf.desy.de/general_naf_docu/interactive_login/ to log into an ATLAS work group server at the NAF. This also includes instructions for Mac users.

Work group server are named tcxXXX. Use the command wgsinfo to get a list of all work group server available to ATLAS.

Login from LXPLUS

In case you want to log on to the NAF from LXPLUS you have to source the GRID environment on the LXPLUS machine by typing 

source /afs/cern.ch/project/gd/LCG-share/current_3.2/external/etc/profile.d/grid-env.sh
voms-proxy-init -voms atlas:/atlas/de -rfc
gsissh -X atlas.naf.desy.de

This will setup the latest minor version of the Grid UI version 3.2. This UI does only work on 64-bit systems.

Login from your laptop

Install the openafs-client and copy the .globus directory on your laptop.

The Grid UI comes in version 3.1 and 3.2. 3.1 is build for SL4 and 32bit, 3.2 is build for SL5 and 64 bit. Please note, that version 3.1 will always run on SL5 and also Ubuntu, but version 3.2 will only run on 64 bit systems (SL5 and Ubuntu). Hence you have to choose the correct UI. uname -a will give you a hint if your system is 32 bit (i686) or 64 bit (x86_64).

You can setup the Grid UI from DESY or CERN:

Finally you need a grid proxy and then can log into the NAF: 

grid-proxy-init -rfc
gsissh -Y atlas.naf.desy.de

Install/setup OpenAFS in Ubuntu

  1. install the needed packages by issuing the commands

    sudo apt-get install krb5-user
sudo apt-get install openafs-client
sudo apt-get install openafs-krb5

  2. set up the client by a) issuing sudo dpkg-reconfigure -plow openafs-client or b) the following steps

    1. modify /etc/openafs/afs.conf.client to look like

      AFS_CLIENT=true
AFS_AFSDB=true
AFS_CRYPT=true
AFS_DYNROOT=false
AFS_FAKESTAT=true

    2. modify /etc/openafs/ThisCell to look like e.g.<<BR> 

      cern.ch

    3. modify /etc/openafs/cacheinfo to look like e.g.

      /afs:/var/cache/openafs:512000

  3. created the needed kernel modules by issuing

    sudo /etc/init.d/openafs-client stop
sudo apt-get install module-assistant
sudo m-a prepare
sudo m-a a-i openafs
sudo /etc/init.d/openafs-client start

  4. now you should be able to uses the afs service
    to get access to your files e.g. at CERN type
    klog username@CERN.CH. If it does not work, try with
    klog.afs username@CERN.CH

    1. If you get en error message like: voms-proxy-init: error while loading shared libraries: libexpat.so.0 you can try the following work-around

      cd /usr/lib
sudo ln -s libexpat.so.1.5.2 libexpat.so.0


      You might have to adapt the release number though!

Dedicated GRID Proxy for the NAF

In order to log into the NAF your GRID proxy needs to be of format version 4. This is achieved by specifying -rfc as option to grid-proxy-init or voms-proxy-init. Format version 4 is nor recognised yet by all GRID application and can cause problems.

With the following aliases (for sh like shells) you can create a separate proxy for login into the NAF. These command should go into $HOME/.zshrc on your own computer. You can also increase the lifetime of your proxy using the -valid option to grid-proxy-init. 

alias grid-proxy-init-naf='X509_USER_PROXY=$HOME/k5-ca-proxy-rfc.pem grid-proxy-init -valid 720:00:00 -rfc'
alias grid-proxy-info-naf='X509_USER_PROXY=$HOME/k5-ca-proxy-rfc.pem grid-proxy-info'
alias ssh-naf='X509_USER_PROXY=$HOME/k5-ca-proxy-rfc.pem gsissh -Y atlas.naf.desy.de'

Then, the procedure for login into the NAF is: 

set up GRID UI
grid-proxy-init-naf
ssh-naf

The following function is a bit more complex, but also smarter. Before calling gsissh, it checks if the proxy is still valid. If not it will call grid-proxy-init to create a new one and then log into the NAF. 

function ssh-naf () {
    # setup your UI, for example
    # source /afs/desy.de/project/glite/UI/etc/profile.d/grid-env.sh >& /dev/null
    grid-proxy-info-naf | grep timeleft | awk '{exit ($3 != "0:00:00")}' && grid-proxy-init-naf
    X509_USER_PROXY=$HOME/k5-ca-proxy-rfc.pem gsissh -Y $* atlas.naf.desy.de
}

Then, the procedure for login into the NAF is even simpler: 

ssh-naf

ATLAS: WorkBook/NAF/GetConnected (last edited 2012-11-28 21:23:32 by WolfgangEhrenfeld)