Advice on upgrading from PostgreSQL 9.0

Hi there,

I'm running the below versions of PostgreSQL and PostGIS at the moment
on a Linux Cluster and was wondering if anyone had any hints or tips
about the best way to upgrade my version of PostgreSQL please? I have
4-5 users who all have quite a large amount data stored.

PostgreSQL 9.0.4 on x86_64-unknown-linux-gnu, compiled by GCC gcc (GCC) 4.1.2 2
0080704 (Red Hat 4.1.2-48), 64-bit

POSTGIS="2.0.4SVN r11660" GEOS="3.3.8-CAPI-1.7.8" PROJ="Rel. 4.6.1, 21
August 2008" GDAL="GDAL 1.10.0, released 2013
/04/24" LIBXML="2.7.6" LIBJSON="UNKNOWN" TOPOLOGY RASTER

Thanks

James