Frequent unbound restarts

Gertjan

I never actuality tested (looked for) this : If a new lease comes in and the option is checked, then unbound is HUPped.
A lease renewal : no, as only the duration is updated, which is not a DNS 'thing'.

jt

how's the BIND implementation currently doing? would switching from unbound help here?

Gertjan

bind check the config file it's using, and parses them when it detect it was 'touched' by some other process.
What I do know is this : it won't ditch the cache when this happens.
It can also unbind and bind to new interfaces, when they come and leave.

But I can't tell if it would be better.
bind is huge. Setup has to been done manually, even if you use a GUI like pfSense uses.
bind needs users to look at the manual (huge also) for sure , otherwise DNS becomes a mess.

I don't bother, practically all my devices on my trusted LAN's have static MAC leases, for IPv4 and IPv6, so 'my' unbound doesn't restarts very often (less then ones a day, probably even less frequent).

Orbixx

I have this problem after adding pfBlockerNG with a significantly large DNSBL list. Will try the following to reduce/eliminate impact:

Reduce pfBlockerNG lists to a more reasonable size
Add more static IP leases where reasonable
Increase lease time

lawrencedol

[Post deleted. My problem is not related to this.]

stephenw10

If you are getting disruption to VoIP calls that's clearly not directly DNS related. It may in fact be nothing to do with Unbound at all and in fact is just a symptom of something else that also causes Unbound to take far longer to reload.
Have you been seeing this before 2.4.5 or just since upgrading? If it's only in 2.4.5 you are probably hitting this:
https://redmine.pfsense.org/issues/10414

Try opening top -aSH and also pinging the firewall and then go to Status > Filter Reload in the gui and reload the filter.
If you see pings spike and processes shoot up to the top of the top table, pfctl, sshd, dpinger etc, then you almist certainly are hitting that.

Steve

lawrencedol

@stephenw10

Appreciate the feedback, thanks. I guess I am still digging on my issue because my son just confirmed to me that my specific problem is not yet resolved.

stephenw10

I'm assuming you are running this at home and don't have a massive number of dhcp clients?

There are thousands of users in the same situation, including me, who are not hitting this. It think it's likely Unbound reloading causing disruption is in fact a symptom of something else rather than a cause.

Steve

lawrencedol

This post is deleted!

stephenw10

Check the cron table, install the Cron package to make it easy. What is running at those intervals?

Steve

lawrencedol

This post is deleted!

jasonArloUser

I have turned off DHCP DNS registration for guest users and so on and I have static DHCP leases for all my known devices but I still have the internet go offline once per day. The fact remains: this is a bug in PfSense that the lease script is calling HUP. It needs to be changed to reload the only the local cache as described above.

stephenw10

This is the open big covering this issue: https://redmine.pfsense.org/issues/5413

There is an open pull request there. dhcpleases is a binary though so would need to be compiled and swapped out to test.

Steve

Gertjan

@jasonArloUser said in Frequent unbound restarts:

I have turned off DHCP DNS registration for guest users and so on and I have static DHCP leases for all my known devices but I still have the internet go offline once per day. The fact remains: this is a bug in PfSense that the lease script is calling HUP. It needs to be changed to reload the only the local cache as described above.

If you remove the check, as shown here :

then process 'dhcpleases' - example :

2930  -  Ss       0:00.01 /usr/local/sbin/dhcpleases -l /var/dhcpd/var/db/dhcpd.leases -d your-local-domain.tld -p /var/run/unbound.pid -u /var/unbound/dhcpleases_entries.conf -h /etc/hosts

will not run : unbound will not get restarted by a new DHCP lease.

If (your) unbound is restarting to often, some other process is responsible for this.

Btw : my 'unbound' process restated 5 days ago - and I guess it was me doing so changing a setting.

@stephenw10 said in Frequent unbound restarts:

This is the open big covering this issue: https://redmine.pfsense.org/issues/5413
There is an open pull request there. dhcpleases is a binary though so would need to be compiled and swapped out to tes

Unbelievable that this issue still exists after 4 years. One might ask : is it really an issue, as circumventing it is rather easy to do ?
Also, unbound is a rather small resolver that handles the job very well.
It 'unbound' that has to be rewritten by the authors so it can reread dynamic its config files if one changes - as the alternative does : bind (named).
But bind has also it's disadvantage. It's huge. And hard to administer it when you hide the option (hunderds) behind a GUI like interface like pfSense.

stephenw10

I have never hit it myself but clearly some people do. Switching to reload instead of restart does seem like the obvious option here. The fact it hasn't happened yet may imply I'm missing something though.

Steve

lucas_nz

@stephenw10 It's particularly noticeable if you are using pfBlockerNG - which adds large lists of sites to the unbound config (to provide DNS based blocking) and thus the reload can take some seconds (the restart wasn't noticeable before I implemented pfBlockerNG). This was a major issue for me until I unticked DHCP registration option. But having DHCP registration disabled is a bit lame.

Luke

stephenw10

I imagine there is a threshold where the latency for the different processes becomes critical. I run pfBlocker and have dhcp leases enabled and never have an issue. I seemingly have not that limit yet.

RichMawdsley

@stephenw10 said in Frequent unbound restarts:

I have never hit it myself but clearly some people do. Switching to reload instead of restart does seem like the obvious option here. The fact it hasn't happened yet may imply I'm missing something though.

Steve

This is what I don't understand either. This seems like a reaaally simple thing to fix.. and yes, I say FIX because this is absolutely a ridiculous flaw.

Gertjan

@lucas_nz said in Frequent unbound restarts:

But having DHCP registration disabled is a bit lame.

Shutting down that option is half the work.
This one stays on :

and you add all your devices to the "DHCP Static Mappings for this Interface" list.

@stephenw10 said in Frequent unbound restarts:

I run pfBlocker and have dhcp leases enabled and never have an issue.

I bet you didn't select "all the feeds" neither ;)

edit : https://redmine.pfsense.org/issues/5413

stephenw10

@Gertjan said in Frequent unbound restarts:

I bet you didn't select "all the feeds" neither ;)

Indeed I did not.