Updating the CASA Data Repository
CASA data repositories contain our current best knowledge of, e.g., observatory coordinates, leap seconds, ephemerides, calibrator models, etc. Every version of CASA contains the latest files as they are available at the time of the release.
Some of this information, like leap seconds, can go out of date since at any time they can only be predicted for a certain time into the future. Also, we only store ephemerides up to a certain future date at release time. Finally, for models etc., an improved version may become available after the release.
So, one may need to manually update the data repository on an existing CASA version if the version is used on data which was taken much later than the CASA release date. From CASA version 4.4 and onwards, one can do this in two different ways (independent of the operating system):
1) On the CASA prompt, run
# In CASA !update-data
2) Without starting CASA one can update the repository from the Unix prompt, too:
# in a terminal casa-config --exec update-data
either command will pull the current data repository from the NRAO database and update it on disk.