Re: qmail unable to chdir to Maildir after Debian upgrade to 'buster'

Hi -

I did it to myself. :)  Thanks kindly to Ed, Erwin, Johannes and anyone
else I may have failed to mention.  Apparently I had changed something in
locals, rcpthosts, or virtualdomains that must have looked right to me
when I did it but wasn't, and it was causing the problem.  I don't quite
understand why "unable to chdir to Maildir" was the particular error
message that was triggered by that, but: All better now. :)  I'm grateful
for the thoughts on AppArmor and the mini-tutorial on htop and strace.

Blessings, all.

--hobie

> Hi,
>
> first, validate that the qmail users in /etc/password are sill ok and are
> migrated ok.
>
> Second, I could suggest to install 'htop' to see the delivery chain of
> qmail-send.
> You should see something like that:
>
> root      3055  3047  0 Jul08 ?        00:00:00 supervise qmail-send
> qmaill    3085  3056  0 Jul08 ?        00:00:00 multilog t s16777215
> /var/log/qmail-send
> qmails   11722  3055  0 Aug02 ?        00:00:00 qmail-send
> root     11737 11722  0 Aug02 ?        00:00:00 qmail-lspawn ./Maildir/
>
> In order to run qmail-lspawn, qmail needs root privileges.
>
> Third, now you can strace this pid
>
> sudo strace -f - <pid> -o <file>
>
> You should catch the output to a file.
>
> As Johannes said: Permission problem due to changed security mechanisms.
>
> Regards.
> --eh.
>
>
>
>> Am 07.08.2019 um 09:00 schrieb hobie of RMN <[email protected]>:
>>
>>> On 2019-08-06 20:02-0400, hobie of RMN wrote:
>>>> Since a very recent upgrade by Debian that moved release 'buster' to
>>>> 'stable', incoming mail can't be delivered, generates the error
>>>> message that qmail now is unable to change to the Maildirs that are
>>>> several levels below /home/vpopmail.  All file permissions appear
>>>> unchanged.  Any idea how to fix this?  Thanks kindly.
>>>
>>> Can you strace the qmail-send and watch what it is doing up to the
>>> error? It might give some clues. What is the exact error from the
>>> delivery log?
>>
>> Thanks. :) Log entry:
>>
>> delivery 94: deferral: Unable_to_chdir_to_maildir._(#4.2.1)/
>>
>> strace is installed but I've never used it.  Is it possible to strace an
>> already-running process?  I'd need directions on how to do it.
>>
>> --hobie
>>
>>
>
> Dr. Erwin Hoffmann | FEHCom | http://www.fehcom.de | PGP Key-Id 7E4034BE
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