[CentOS] Enabling MD5 (longer passwords) after installation?

> Does it matter when I run it? I mean before or after pwconv/grpconv,
> assuming I still need to use them?

Here's what I would do:

pwunconv
grpunconv
authconfig
pwconv
grpconv

Probably not entirely necessary, but does it hurt anything?  The crypts 
will be available to local users from the time you run *unconv until you 
run the *conv.

j