> On 10 April 2019 23:13 Laura Smith via dovecot <dovecot@dovecot.org> wrote: > > > Sent with ProtonMail Secure Email. > > ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ > On Wednesday, April 10, 2019 8:20 PM, Aki Tuomi <aki.tu...@open-xchange.com> > wrote: > > > > On 10 April 2019 22:13 Laura Smith via dovecot dovecot@dovecot.org wrote: > > > On Wednesday, April 10, 2019 7:57 PM, Aki Tuomi > > > aki.tu...@open-xchange.com wrote: > > > > > > > > On 10 April 2019 21:26 Laura Smith via dovecot dovecot@dovecot.org > > > > > wrote: > > > > > > > > > > ========================================================================== > > > > > > > > > > dsync(foo...@example.com): Error: imapc(foobar.example.com:993): > > > > > dns_lookup(foobar.example.com) failed: > > > > > read(/var/run/dovecot/dns-client) failed: read(size=512) failed: > > > > > Connection reset by peer > > > > > > > > This is dovecot's internal dns-client, and something goes wrong when > > > > talking to the service. > > > > > > > > > dsync(foo...@example.com): Error: Failed to initialize user: imapc: > > > > > Login to foobar.example.com failed: Disconnected from server > > > > > > > > This is btw dsync service, not imap service. > > > > > > > > > === > > > > > Initially I thought "oh no, not another AppArmor block". > > > > > But then surely the second message would not appear if the DNS lookup > > > > > was not successful ? > > > > > Also "dig foobar.example.com" works fine. > > > > > How should I be troubleshooting this ? And if it is still likely to > > > > > be AppArmor, what is calling it ? "doveadm" itself or something else > > > > > ? What does "/var/run/dovecot/dns-client" do and why doesn't dovecot > > > > > use standard OS calls like everyone else ? > > > > > > > > Because the "standard OS call" is blocking and we would prefer it to > > > > not block everything else. > > > > > > > > > So many questions ! > > > > > > > > Aki > > > > > > Thanks for your reply, but both those message are generated from a simple > > > : > > > doveadm -v -o mail_fsync=never backup -R -u foo...@example.com imapc: > > > So I don't know what you mean about dsync service failing ? Surely the > > > DNS lookup succeeded if the 'dsync service' failed due to remote > > > disconnect ? > > > I'm still none the wiser as to where to start looking for troubleshoting ? > > > > Did you check dovecot logs? Maybe there is something useful? > > > > Aki > > > Only the same old cryptic message about dns-client ? > master: Fatal: execv(/usr/lib/dovecot/dns-client) failed: Permission denied
Something prevents executing the dns-client binary. > master: Error: service(dns_client): command startup failed, throttling for 16 > secs > dns_client: Fatal: master: service(dns_client): child 14293 returned error 84 > (exec() failed) Aki
