Jul 21 18:24:02 dns02 systemd[1]: Started Knot DNS Resolver daemon.
Jul 21 18:24:02 dns02 systemd[1]: kresd.service: Got notification message from PID 23544, but reception only permitted for main PID 23542
Jul 21 18:24:02 dns02 kresd[23542]: [ ta ] warning: overriding previously set trust anchors for .
Jul 21 18:24:02 dns02 systemd[1]: kresd.service: Got notification message from PID 23545, but reception only permitted for main PID 23542
Jul 21 18:24:02 dns02 kresd[23542]: [ ta ] warning: overriding previously set trust anchors for .
Jul 21 18:24:02 dns02 systemd[1]: kresd.service: Got notification message from PID 23546, but reception only permitted for main PID 23542
Jul 21 18:24:06 dns02 kresd[23542]: mdb.c:3118: Assertion 'pglast <= env->me_pglast' failed in mdb_freelist_save()
Jul 21 18:24:06 dns02 systemd[1]: kresd.service: Main process exited, code=killed, status=6/ABRT

kometch@dns02:~$ sudo systemctl status kresd
● kresd.service - Knot DNS Resolver daemon
Loaded: loaded (/etc/systemd/system/kresd.service; enabled; vendor preset: enabled)
Active: deactivating (stop-sigterm) (Result: signal) since Fri 2017-07-21 18:28:46 JST; 8s ago
Docs: man:kresd(8)
Process: 26158 ExecStart=/usr/sbin/kresd $KRESD_ARGS (code=killed, signal=ABRT)
Main PID: 26158 (code=killed, signal=ABRT)
CPU: 8.941s
CGroup: /system.slice/kresd.service
└─26160 /usr/sbin/kresd -c /etc/knot-resolver/kresd.conf -v -f 4 -k /etc/knot-resolver/root.key /var/knot-resolver

Jul 21 18:28:36 dns02 systemd[1]: Started Knot DNS Resolver daemon.
Jul 21 18:28:36 dns02 kresd[26158]: [ ta ] warning: overriding previously set trust anchors for .
Jul 21 18:28:36 dns02 systemd[1]: kresd.service: Got notification message from PID 26159, but reception only permitted for main PID 26158
Jul 21 18:28:36 dns02 kresd[26158]: [ ta ] warning: overriding previously set trust anchors for .
Jul 21 18:28:36 dns02 systemd[1]: kresd.service: Got notification message from PID 26161, but reception only permitted for main PID 26158
Jul 21 18:28:36 dns02 systemd[1]: kresd.service: Got notification message from PID 26160, but reception only permitted for main PID 26158
Jul 21 18:28:40 dns02 kresd[26158]: mdb.c:3118: Assertion 'pglast <= env->me_pglast' failed in mdb_freelist_save()
Jul 21 18:28:46 dns02 kresd[26158]: mdb.c:3118: Assertion 'pglast <= env->me_pglast' failed in mdb_freelist_save()
Jul 21 18:28:46 dns02 kresd[26158]: mdb.c:3118: Assertion 'pglast <= env->me_pglast' failed in mdb_freelist_save()
Jul 21 18:28:46 dns02 systemd[1]: kresd.service: Main process exited, code=killed, status=6/ABRT