unboud stops multiple times per day, due to part of Router Advertisement expired

[Peter Russell]

Thank you for your reply

I agree that it's probably the DHCP daemon that triggers unbound to restart,
not directly, but because unbound detects a routing change.
Since there is a syslog message from the daemon (dhcpcd[562]: eth0: part of
Router Advertisement Expired), it is the probable cause for unbound to
restart.

However (1) the message says part of the routing expired, shouldn't unbound
ignore expired routes?

However (2) , as I mentioned before, unbound restarts twice, every time this
happens.
There is nothing I can find that would explain the second restart.
So this looks like something unbound is doing, without any external event or
command.

I very much doubt it is an unbound-control command, these are logged in the
unbound log.
Not sure if SIGHUB signals are logged...

-----Original Message-----
From: Unbound-users [mailto:unbound-users-bounces at lists.nlnetlabs.nl] On
Behalf Of George Thessalonikefs via Unbound-users
Sent: Monday, 17 May, 2021 2:45 PM
To: unbound-users at lists.nlnetlabs.nl
Subject: Re: unboud stops multiple times per day, due to part of Router
Advertisement expired

Hi Peter,

Unbound does not restart on its own.
I suspect that the DCHP daemon (or something else on your system) instructs
unbound to reload (either with SIGHUP or via unbound-control
reload) when there is a DHCP update.

I would advise to look at the DHCP configuration for further
troubleshooting.

Best regards,
-- George

On 14/05/2021 19:30, Peter Russell via Unbound-users wrote:
> Unbound 1.13.1, with ./configure --prefix=/usr --sysconfdir=/etc 
> --disable-static --enable-tfo-client --enable-tfo-server 
> --with-libevent --with-libhiredis --enable-cachedb 
> --with-pidfile=/run/unbound.pid
> 
> The log shows, multiple times per day:
> 
> May 14 06:15:26 unbound[790:0] info: service stopped (unbound 1.13.1).
> 
> info: server stats for thread 0: 0 queries, 0 answers from cache, 0 
> recursions, 0 prefetch, 0 rejected by ip ratelimiting
> 
> info: server stats for thread 0: requestlist max 0 avg 0 exceeded 0 
> jostled 0
> 
> info: mesh has 1 recursion states (0 with reply, 1 detached), 0 
> waiting replies, 0 recursion replies sent, 0 replies dropped, 0 states 
> jostled out
> 
> info: server stats for thread 1: 0 queries, 0 answers from cache, 0 
> recursions, 0 prefetch, 0 rejected by ip ratelimiting
> 
> info: server stats for thread 1: requestlist max 0 avg 0 exceeded 0 
> jostled 0
> 
> info: mesh has 0 recursion states (0 with reply, 0 detached), 0 
> waiting replies, 0 recursion replies sent, 0 replies dropped, 0 states 
> jostled out
> 
> info: server stats for thread 2: 0 queries, 0 answers from cache, 0 
> recursions, 0 prefetch, 0 rejected by ip ratelimiting
> 
> info: server stats for thread 2: requestlist max 0 avg 0 exceeded 0 
> jostled 0
> 
> info: mesh has 0 recursion states (0 with reply, 0 detached), 0 
> waiting replies, 0 recursion replies sent, 0 replies dropped, 0 states 
> jostled out
> 
> info: server stats for thread 3: 0 queries, 0 answers from cache, 0 
> recursions, 0 prefetch, 0 rejected by ip ratelimiting
> 
> info: server stats for thread 3: requestlist max 0 avg 0 exceeded 0 
> jostled 0
> 
> info: mesh has 0 recursion states (0 with reply, 0 detached), 0 
> waiting replies, 0 recursion replies sent, 0 replies dropped, 0 states 
> jostled out
> 
> notice: Restart of unbound 1.13.1.
> 
> unbound than almost always immediately stops a second time:
> 
> May 14 06:15:27 unbound[790:0] info: service stopped (unbound 1.13.1).
> 
> verbosity 1, which, according to the manual, should display all errors.
> 
> I've narrowed it down to a specific matching syslog entry:
> 
> The syslog entries:
> 
> May 14 06:15:26 raspberrypi dhcpcd[562]: eth0: part of Router 
> Advertisement expired
> 
> May 14 07:09:04 raspberrypi dhcpcd[562]: eth0: Router Advertisement 
> from fe80::20e:c4ff:fecf:f3cf
> 
> May 14 07:09:04 raspberrypi dhcpcd[562]: eth0: Router Advertisement 
> from fe80::20e:c4ff:fecf:f3cf
> 
> May 14 14:53:25 raspberrypi dhcpcd[562]: eth0: part of Router 
> Advertisement expired
> 
> The unbound entries:
> 
> May 14 06:15:26 unbound[790:0] info: service stopped (unbound 1.13.1).
> 
> May 14 06:15:27 unbound[790:0] info: service stopped (unbound 1.13.1).
> 
> May 14 14:53:25 unbound[790:0] info: service stopped (unbound 1.13.1).
> 
> May 14 14:53:29 unbound[790:0] info: service stopped (unbound 1.13.1).
> 
> Notice the time match, part of Router Advertisement expired apparently 
> triggers an unbound restart
> 
> the IPv4 address is served by a static (MAC based) entry, thus never 
> changes.
> 
> the IPv6 address is served by a pfsense firewall (configured with 
> 'track interface'), never changes, unless ISP resets... (didn't happen
today).
> 
> There is really nothing I can do about the IP address assignment.
> 
> Not sure how to proceed from here, I don't understand why an expired 
> route causes unbound to restart
>