Following on from part 2 of this series, is the requirement that e-mail must leave the system it's generated on, unless it's going to a mailbox on the local system which is actively monitored (weekly minimum, preferably every week-day or maybe even several times a day). Typically that place will only be on your actual mail server. In general, system mail must go to a real IMAP/POP/Exchange/LotusNotes/Whatever mailbox server (MDA), where someone' mail client will present it to them.

Quick entry today:

You can still use sudo when already root, so if for example you have to be root to trawl around in restricted directories in ways you can't with efficiently do with "sudo ls", you can and should still use "sudo " for actual operations, as it leaves a log trail for later (and can be traced to you by the original sudo on that terminal).

Systems should be silent, unless they have something important to say that requires action on the part of the system administrator. In particular, notifcations (e.,g. e-mails, but potentially other mechanisms) should only be sent if they require action. If the action required is not completely obvious from the direct contents of the notification, then you need to add a link to external documentation detailing what needs to happen (e.g. a "trouble code", or a link to your wiki etc).

I've been a system administrator for nearly 10 years now, and there's a few things I've learned along the way. This is the first in a series of short posts sharing some of these things.