Setting your time zone
======================

.. toctree::
   :maxdepth: 1
   :caption: Contents:

.. warning:: The local time zone set on all Discoverer HPC login and compute nodes is ``Europe/Sofia``.

.. note:: The supported time zone catalogue is located under ``/usr/share/zoneinfo``. It is maintained by the package tzdata.

In your profile (bash)
----------------------

In case you need to change the time zone under your Linux account on Discoverer HPC, browse the catalogue under ``/usr/share/zoneinfo``:

.. code:: console

 ls /usr/share/zoneinfo

then assign the zone name to the shell environment variable ``TZ`` (to make the changes permanent, do that assignment in your ``~/.basrc`` file):

.. code:: console

 export TZ=Europe/Zurich

Here ``Europe/Zurich`` is given as an example.

In case you want to switch to UTC:

.. code:: console

 export TZ=UTC

In your Slurm batch scripts
---------------------------

.. important:: Changing time zone does not affect the execution time of your Slurm jobs. It can only provide time zone specific time to the jobs, if they need it (which is a very rare case).

See the exaplanations for setting the time zone for your bash profile given above. If you do not want to change the time zone in your bash profile, then specify the export declaration within the particular Slurm batch script:

.. code:: console

 export TZ=UTC

For you cron jobs
-----------------

.. important:: By default, the execution time specified for cron job is relative to the time zone set at a system level (``Europe/Sofia``).

If you want to set your cron job execution time relative to another time zone, different than the default one (EST/EEST), check first if that zone name is listed under ``/usr/share/zoneinfo``, and if it is available there, set its name a value to the variable ``CRON_TZ`` in the crontab description, right before the job declaration:

.. code:: console

 CRON_TZ=UTC
 00 01 * * * /discofs/username/cron/job1.bash