Corrupt mail files

[Tom Metro]

david-8uUts6sDVDvs2Lz0fTdYFQ at public.gmane.org wrote:
> The beginning of the file is a series of zeroes...
> ~# od -ch /var/mail/susan | head -10
> \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
> (StrongMail Ente
> rprise 3.2.3.3(3
> .00.320)); Thu,
> 11 Jun 2009 09:0

It looks like not only is the start of the message overwritten with a 
string of 16 nulls, but the remainder of the string appears to be a 
Received line, with no sign of the From_ line (typically longer than 16 
bytes), so it looks like the message is truncated as well (or the From_ 
line was missing).


> - It could be that I'm using ext4, which might not have been a smart thing.

This, or a hardware problem, seems most likely, given the mail tools are 
all fairly mature and reliable. You might want to test this out 
temporarily by symlinking the spool to another file system or an NFS mount.

I've been seeing mention of ext4 problems in Ubuntu bug reports. 9.04 is 
shaping up to be rather buggy.


> - It could be procmail, but that seems unlikely to me. .procmail doesn't
> even have an explicit thing that writes to /var/mail/susan.

If procmail is being used for local delivery, then it will implicitly 
write to the spool. Check your postfix master.cf to see what local 
delivery agent is being used.


> - It could be that I'm using MBox instead of Maildir....

Mbox may be inefficient for some operations, but it known for corruption.


> But that doesn't affect the inbox, just the saved IMAP
> folders, right?

As another poster mentioned, it is typical to set up a local delivery 
agent to use Maildir for the inbox.

I'd hold off on the conversion until you've tracked down the source of 
your corruption.  Once that's behind you, consider switching to 
Dovecot's deliver as your LDA, unless you have a lot of custom procmail 
filtering you don't want to convert to Seive.

  -Tom

-- 
Tom Metro
Venture Logic, Newton, MA, USA
"Enterprise solutions through open source."
Professional Profile: http://tmetro.venturelogic.com/