After installing RH7.1, I noticed that all deliveries to mailbox files of
50Mb started failing. After some kludging around with procmail (which
really should log errno on failed writes), I noticed that postfix's
mailbox_size_limit was being passed to procmail as a RLIMIT_FSIZE.
Setting mailbox_size_limit to an arbitrary large value worked around the
problem for me, but postfix should be fixed to reset rlimit before firing
off the LDA.
AFAIK that's just intended behaviour. That's what mailbox_size_limit is for in
the first place.
It wasn't expected behaviour in any case (I would expect an implicit size limit
to apply only to postfix's own LDA), and it was painful to debug because
procmail doesn't log errno for failed writes to mboxes even in verbose mode.
intended (by the author) != expected (by the user)
We had this discussion on postfix-user mailinglist. Wietse's mails lead me to
the claim that it is _intended_ behaviour by the author.
If you want to have different semantics you've got to contact Wietse
(firstname.lastname@example.org) or even better discuss on postfix-users mailing list.
I still think RESOLVED/NOTABUG is the correct resolution.
BTW: you can disable the limit by
mailbox_size_limit = 0