To do this on an Ubuntu machine is relatively easy.
Just run the following commands.
First log in as the postgres user
> sudo
su postgres
|
Then run pg_dumpall and pipe it to a compression program, in
my case I use bzip2
> pg_dumpall | bzip2 -vf > database.`date
+"%Y.%m.%d"`.pgdumpall.bz2
|