[lug] postfix aliases, best practices?

[bgiles at coyotesong.com]

I think you need an entry for every account in /etc/passwd.  I don't
recall, off the top of my head, how to only define the accounts
internally.

> I've seen every single one of the accounts from system
> services (such as those listed in /etc/aliases, but not just from there)
> being blindly tested for ssh cracking purposes

/etc/ssh/sshd_config AllowUsers