Sorry, I got the sudo command wrong. Confused sudo and su.sudo -u postgres pg_dumpall > /tmp/mypgbackup.sqlcp /tmp/mypgbackup /home/myuser/
When I do a reboot or a halt it does say that postgres 9.3 is being halted in the shutdown sequence so I don't know what's the issue here.
Thanks for the help!!
Darald