An account on the I-Cluster2 is created for each scientific project
validated by the I-Cluster2 committee.
We ask you to fill the register form to introduce yourselves and present the purpose of you activities on the cluster.
You must fill the I-Cluster2 Login Application Form to present your scientific project.
Please provide information as accurate as possible when filling form.
The registration information is kept private and will not be disclosed to third parties, except project name and URL which should be publish on I-Cluster2 web site as project user.
I-cluster2 is reachable using ssh onto frontal
From this machine, you although have to connect on nodes by using oar commands to compile or launch jobs on the cluster.
All development work must be done on the cluster nodes not from the frontal node (ita.imag.fr)
Intel® C/C++ Compiler : icc/icpc
Intel® Fortran Compiler : ifort
Intel® Debugger : idb
OAR is a PBS-like system. Thus, it is useful to have some knowledge concerning this kind of cluster tool. As it provides a PBS-compatible software interface, it should not be difficult to work with it. This page gives an overview of the most used tools. For further information, I suggest you read the manual. ;-)
Once you're connected to the front-end server (ita), you can use the following commands.
oarnodes displays the state of the cluster : which nodes are up and ready, which are not available for OAR. It does not require any argument.
oarstat gives the list of the OAR running jobs on the whole cluster. No arguments.
The most useful command. It is used to submit a job. You may specify the number of nodes to use or the maximum walltime the job should run. OAR will select the node names according to the cluster availability
There are two ways to use oarsub : interactive and passive.
The interactive way allows you to open a shell on a cluster node and type your commands. When you quit this shell, your job finishes and the node is freed for other users. In order to select the interactive mode, use the -I flag in your oarsub command. The following example is roughly equivalent to a rsh to a free node :
The passive mode is used to schedule batch and time-consuming jobs. To use this mode, you have to provide a program or script name as the last argument of your oarsub command. Example :
Once your job is done, you will find two files per node allocated for your job. They are named after the following scheme:
You should read them to get the result of your job.
Warning : the commands and softwares used in the script must be available on each nodes concerned by your job. It could be software in a NFS-exported directory.
In addition to the submission mode, you can specify several requirements for your job. Some examples :
To reserve the ita12 nodes :
oarsub -p "hostname='ita12.imag.fr'" submission mode
To reserve ita10 to ita19 :
oarsub -l nodes=10 -p "hostname like 'ita1_.imag.fr'" submission mode
To reserve 20 nodes on the same switch (fast ethernet) number 2:
oarsub -l nodes=10 -p "switch = '2' " submission mode
oardel deletes a job identified by its ID (oarstat).