> On 30/03/2020 18:32 t...@linux-daus.de wrote: > > > Hi Aki, > > > Aki Tuomi <aki.tu...@open-xchange.com> hat am 30. März 2020 16:23 > > geschrieben: > > > > Can you install dovecot-dbg to get debug symbols, open the core in gdb and > > run > > > > bt full > > > > Full backtrace: >
<snip /> > > Best regards, > Tim It seems that your configuration ends up passing empty host from the user lookup to DNS resolve. This should be handled earlier of course, if this is really the case. Do you have any idea which user is triggering this based on logs? You could try 'doveadm auth lookup <username>' to see if you are getting bad values? Are you able to turn on 'auth_debug=yes', I understand it might be high volume with 7k logins. Aki