===== Interactive Jobs =====
To start an interactive use the **''qsub''** command with the **''-I''** option: 
<code>
razor-l1:pwolinsk:$ qsub -I 
qsub: waiting for job 1451274.sched to start
qsub: job 1451274.sched ready

PBS_NODEFILE=/var/spool/torque/aux/1451274.sched PBS_NUM_NODES=walltime=03 PBS_PPN=walltime=03:00:00 PBS_PPA=12
Currently Loaded Modulefiles:
  1) os/el6
compute1141:pwolinsk:$ 
</code>

This command starts an interactive job with default parameters:
 
   * 1 core on 1 node on the ''tiny12core'' queue for 3 hours 

To explicitly specify these options please use the following parameters to the qsub command.

^ parameter ^ value ^ meaning ^
| ''-I'' |                      | (uppercase "i") request an interactive job |
| ''-l'' | ''walltime=2:01:00'' | (lowercase "L") request a runtime of 2 hours 1 minute and 0 seconds |
| ''-l'' | ''nodes=1:ppn=2''    | (lowercase "L") request 2 computing cores on 1 node |
| ''-q'' | ''student48core''    | request a node in the 'student48core' queue |

  
<code>razor-l1:pwolinsk:$ qsub -I -l walltime=2:01:00 -l nodes=1:ppn=2 -q student48core
qsub: waiting for job 1451283.sched to start
qsub: job 1451283.sched ready

PBS_NODEFILE=/var/spool/torque/aux/1451283.sched PBS_NUM_NODES=1 PBS_PPN=2 PBS_PPA=48
Currently Loaded Modulefiles:
  1) os/el6
compute2801:pwolinsk:$ 
</code>

For information about the available queues on Razor and Trestles please see [[queues|]].

Interactive jobs end when you disconnect.  If your job is done computing and is at a system prompt, please exit the compute node so it can be reused. If you have unreliable network access that doesn't last as long as an interactive job, see [[http://research.computing.yale.edu/support/hpc/user-guide/preserve-session-screen|GNU Screen at Yale CRC]].