Is there a best practice of migrating django app from ubuntu server to red hat? What could be the challenges?
In the same vein will postgreSQL migration pose any challenges?
Personally I've had my very basic Django based app switching between Ubuntu/RedHat/Debian/Windows. I've not had any OS platform specific problems (only using Django and Django-pagination). I built and installed Django from the sources at www.djangoproject.com each time (ubuntu had 0.99 for a long time and I wanted 1.0), I only used deb and rpm packages for python. My DB has been MySQL not PostgreSQL but I've not had any problems with it. My advice would be to keep a very close eye on version numbers for things like wsgi, python interpreter etc., if you have a test suite or the time to write one then that can be very reassuring when you migrate to a different platform to see the same results. Get some benchmarks before you move the site and compare them.