gpg: failed to create temporary file '/var/lib/lurker/.#lk0x56a84100.hantslug.org.uk.11042': Permission denied
gpg: keyblock resource '/var/lib/lurker/pubring.gpg': Permission denied
gpg: Signature made Thu May 7 06:30:00 2026 BST
gpg: using RSA key 898A78DCF0DC9B14FF90997EB472A863FC94FD2A
gpg: Can't check signature: No public key
On 05/05/2026 17:01, Hants LUG via Hampshire wrote:
> Hello all…
G'day :-)
>
> The TLDR; is - First time poster here, hoping that someone might be able
> to direct me to a guide to help me install a Postfix/Dovecot/MariaDB
> setup on a Raspberry Pi 4B running Trixie please?
>
>
> I appreciate that’s exceedingly brief, so in the hope that it will help,
> here’s (quite a bit) more detail…
>
> In readiness for the (hopefully soon) arrival of FTTP, I’d like to get
> some experience with a locally-hosted mail service and would like to
> build out some Raspberry Pi infrastructure to that effect.
>
> Current setup:-
>
> * Nominated Mail Server Host – Raspberry Pi 4B / running “Trixie”
> * Proposed MTA – Postfix (“Compatability Level 3.6”)
> * Proposed MDA/IMAP/POP3 – Dovecot 2.4.1-4
> * Proposed SQL Server – MariaDB 11.8.5 [hosted on primary QNAP NAS]
> * Existing DNS Infrastructure – Technitium DNS running on a Primary/
> Secondary pair of Pi4Bs...
>
> Current State of Play:-
>
> * I have set up most of the requirements DNS – all but the DKIM record…
>
> * I have [I think!] successfully installed and configured Postfix,
> using this guide:-
>
> https://raw.org/tutorial/seting-up-email-server-with-postfix-
> dovecot-and-mysql/
>
> * I’ve been able to get a MariaDB database configured and populated
> and to use the “postmap -q” command to ensure that PostFix has the
> ability to access the “Domain”, “User”, and “Alias” tables – all
> that test OK.
>
> * I’ve followed the guide all the way through editing Dovecot – the
> section on the above-linked page that has the sub-title, “Update
> Dovecot Configuration Files” – and then in that part of the guide
> and depending on your viewpoint, I am getting stuck and either Step
> 4 [Edit /etc/dovecot/conf.d/auth-sql.conf.ext] or Step 5 [Edit /etc/
> dovecot/dovecot-sql.conf.ext]… in that when I add the edits
> described in Step 4 I get errors reported within the “passdb”
> clause… or, if I comment that out, I find that the file /etc/
> dovecot/dovecot-sql/conf.ext simply doesn’t exist in the Raspberry
> Pi package.
>
> However, given that the file defined in Step 5, above, appears to be
> explicitly named and linked from Step 4, I did try to simply create an
> empty file and populate it as specified… but the error I get suggests
> that I am missing some “syntactic wrapping” – headers, block
> definitions, or similar. More specifically, I see this in syslog:
>
> /“dovecot[20420]: doveconf: Fatal: Error in configuration file /etc/
> dovecot/conf.d/auth-sql.conf.ext line 186: passdb_args: Unknown
> setting: passdb_args (passdb_passdb_args or passdb_sql_passdb_args
> not found either.)”/
>
I recently upgraded my Bookworm hosted server to Trixie, and found the
config file format has changed incompatibly between Dovecot 2.3 and 2.4.
So a lot of the guides out there are now incorrect.
For example, in /etc/dovecot/conf.d/10-auth.conf:
auth_default_realm = teched-creations.com
becomes
auth_default_domain = teched-creations.com
>
> This is the relevant section of the auth-sql.conf.ext file:
>
> passdb sql {
> driver = sql
> args = /etc/dovecot/conf.d/dovecot-sql.conf.ext
> }
So this changed too - instead of referencing yet another config file, my
file has:
sql_driver = pgsql
pgsql localhost {
parameters {
dbname=dovecot
user=dovecot
password=THEPASSWORD
}
}
passdb sql {
default_password_scheme = SHA256
query = \
SELECT username AS user, domain, password
FROM users WHERE (username = '%{user|username}' AND domain =
'%{user|domain}')
}
> userdb static {
> driver = static
> args = uid=vmail gid=vmail home=/var/mail/vhosts/%d/%n
> }
>
> The error I get in Step 4 – before commenting it out – is an error on
> the line that begins “args =” in the sample code listed with that step.
>
> My sense is that a big part of my struggle [other than ignorance] is the
> slight deviation in package layout between my Pi setup and the worked
> examples.
>
Nope, it's the 2.3 vs 2.4 config layout. Both the format of the dict and
the formatting used to interpolate strings changed ( '%u' is now
'%{user|username}', for example):
userdb static {
fields {
uid=vmail
gid=vmail
home=/var/mail/vhosts/%{user|domain}/%{user|username}
}
}
> I have looked at e.g. mail-in-a-box, Citadel, and others and I’m not
> opposed to using a different software stack if someone can make a good
> recommendation… this is just where I’ve got to so far.
>
> Any recommendations for a workable how-to guide for an Intranet Pi
> running a local mail solution would be gratefully received.
>
> Thanks in advance.
>
>
>
Hope this helps!
Cheers
Brad
--
Brad Macpherson
