Suppose that you have a software RAID array. Suppose further that youhave a disk or two fail spectacularly; they don't just have errors, theygo offline completely.

Naturally, software RAID fails the disks out; you wind up with somethingin /proc/mdstat that looks like this:

md10 : active raid6 sdbd1[12] sdbc1[11] sdbb1[10] sdba1[9]sdaz1[13](F) sday1[

Here is a thought that just crystallized for me:

In operations, crud rains down out of the sky and the sysadmins haveto make it go and keep it going.

In system administration, at least you get to design and build thecrud yourself.

(Corollaries about things you inherit from a previous sysadmin whenyou move into an existing environment are left as an exercise for thereader.)

Making Exim discard things in general is simple: you create an Eximrouter using the redirect driver that blackholes messages, and guardit with a suitable set of conditions. I decided to be safe, so we onlydiscard locally generated bounces of spam that are going to an outsidedomain.

(You can detect locally generated bounces with the condition ' and{{!eq{$interface_port}{25}} {!def:return_path}} '. The easy way todiscard messages is