#1137171 kdeconnect: mDNS listener conflicts with systemd-resolved and avahi-daemon

Package:
kdeconnect
Source:
kdeconnect
Description:
connect smartphones to your desktop devices
Submitter:
Tj
Date:
2026-05-20 10:41:01 UTC
Severity:
normal
#1137171#5
Date:
2026-05-20 10:39:02 UTC
From:
To:
Kdeconnect causes mDNS address publishing services (systemd-resolved,
avahi-daemon) to change the published hostname and therefore break
discoverability and connectivity using the known hostname.

After a user session has logged in and as a result the user session service
has started:

 app-org.kde.kdeconnect.daemon@autostart.service

Restarting systemd-resolved (that is managing mDNS publishing) breaks
host discovery due to:

E495-A systemd-resolved[65393]: Detected conflict on E495-A.local IN AAAA fe80::9a7d:5041:7b61:53fd
E495-A systemd-resolved[65393]: Hostname conflict, changing published hostname from 'E495-A' to 'E495-A5'.

Checking the ports shows kdeconnect is using 5353:

tj@E495-A:~$ sudo ss -tunlp 'sport = 5353'
Netid          State           Recv-Q          Send-Q                     Local Address:Port                     Peer Address:Port          Process
udp            UNCONN          0               0                                0.0.0.0:5353                          0.0.0.0:*              users:(("systemd-resolve",pid=65769,fd=15))
udp            UNCONN          0               0                                   [::]:5353                             [::]:*              users:(("systemd-resolve",pid=65769,fd=16))
udp            UNCONN          0               0                                      *:5353                                *:*              users:(("kdeconnectd",pid=66103,fd=20))

I found upstream reports about this that also affects avahi-daemon in
the same way.

https://bugs.kde.org/show_bug.cgi?id=487719

The workaround is to stop the kdeconnect user session service before
restarting resolved/avahi and start it after.