Comment 3 for bug 483768

Networking shutdown is currently not handled by upstart in all cases, so there's no way to stop portmap after the remote filesystems are unmounted but before the network is stopped. As a result, we need to leave portmap running until the end because there's no other way to make sure it stays running as long as it needs to be.

root@AX2-5200p:/etc/init# grep "stop.*portmap" *
gssd.conf:stop on (stopping portmap or runlevel [06])
statd.conf:stop on stopping portmap

This indicates that the two services should be stopped whenever portmap is stopped. portmap can be stopped manually.