unbound continually stopping/starting

[veldthui]

My DNS resolver turned itself off suddenly for no reason so I checked the DNS resolver log and found that unbound seems to be stopping and starting continually.
Is this normal or do I have an issue? I can't see any other issue and it seems to be working after I restarted unbound service.
I do have pfBlocker NG installed but updates are set for 1 hour.

Nov 23 15:49:44	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 15:49:44	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 15:49:50	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 16:03:42	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 16:03:48	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 16:13:55	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 16:14:01	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 16:37:51	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 16:37:57	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 16:43:57	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 16:44:03	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 17:37:51	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 17:37:57	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 17:37:58	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 17:38:04	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 17:43:58	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 17:44:04	unbound	29584:0	info: start of service (unbound 1.9.1).
Nov 23 18:03:43	unbound	29584:0	info: service stopped (unbound 1.9.1).
Nov 23 18:03:49	unbound	29584:0	info: start of service (unbound 1.9.1)

[Gertjan]

Check other logs, like DHCP.

And check this :

if this option is checked, then for every new lease, the Resolver will get restarted.