Slow DNS after 22.05

Gertjan

If you have to forward to some DNS resolver then the quality of your DNS depends on what this DNS server is answering you.

If you decide to use the pfSense default DNS setting, pfSense resolves for you using the 13 ( ! ) available root servers, then DNS will work fine.
I can tell, as I'm using the settings Netgate proposes by default : never had an issue for the last 10+ years.

These settings (first and third) are not default :

"for historical reasons".

tentpiglet

@gertjan

My pfSense DNS resolver settings were the 'default' ones provided out of the box. I made no special modifications. DNS resolution was incredibly unstable.

Switching to the pi-hole container resolved my issues.

johnpoz

@tentpiglet said in Slow DNS after 22.05:

DNS resolution was incredibly unstable.

Do you have IPv6? Other thread around here seems that setting unbound not to use IPv6 in its queries has helped..

server:
do-ip6: no

Gertjan

@tentpiglet said in Slow DNS after 22.05:

pfSense VM running on my Proxmox server

22.05 or 2.6.0 ?

UNstable means :
You found it 'not running', and no process 'unbound' was present when you list processes ?
Or the process unbound was there, but didn't answer ?
An nslookup from a PC on a LAN failed ?

C:\Users\gwkro>nslookup
Server default :   pfSense.main.net
Address:  192.168.1.1

> facebook.com
Server :   pfSense.main.net
Address:  192.168.1.1

Réponse ne faisant pas autorité :
Nom :    facebook.com
Addresses:  2a03:2880:f15a:83:face:b00c:0:25de
          31.13.77.35

>

edit : how many times a day unbound restarts ?
Just ask your pfSense :

grep 'start' /var/log/resolver.log
......
<30>1 2022-07-28T09:31:43.284577+02:00 pfSense.main.net unbound 60716 - - [60716:0] info: start of service (unbound 1.15.0).
<30>1 2022-07-29T14:35:14.991568+02:00 pfSense.main.net unbound 47871 - - [47871:0] info: start of service (unbound 1.15.0).
<30>1 2022-07-29T14:39:18.227880+02:00 pfSense.main.net unbound 94551 - - [94551:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-01T00:00:42.825487+02:00 pfSense.main.net unbound 7853 - - [7853:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-03T10:22:14.251824+02:00 pfSense.main.net unbound 20236 - - [20236:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-03T10:22:52.446334+02:00 pfSense.main.net unbound 82360 - - [82360:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-03T11:04:04.591690+02:00 pfSense.main.net unbound 88564 - - [88564:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-04T08:02:35.997090+02:00 pfSense.main.net unbound 14697 - - [14697:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-04T10:59:24.370800+02:00 pfSense.main.net unbound 59771 - - [59771:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-06T10:09:10.552646+02:00 pfSense.main.net unbound 67115 - - [67115:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-08T00:00:44.809011+02:00 pfSense.main.net unbound 9808 - - [9808:0] info: start of service (unbound 1.15.0).
<30>1 2022-08-09T10:35:25.013811+02:00 pfSense.main.net unbound 44307 - - [44307:0] info: start of service (unbound 1.15.0).

Mikymike82

@gertjan My PFsense was until the upgrade to 22.05 in "standard config" I have never changed anything to my DNS. I even did a complete new installation to replicate the issue. 22.01 no problems and after upgrading to 22.05 my dns resolution was a complete mess.

Jax

Really, I think it's clear something broke in 22.05 and there's not any point in pretending it's a user problem. We've all experienced this and found some work arounds. Perhaps the maintainers should take a serious look at the code and try to figure out why so many users experienced the same phenomenon.

Mikymike82

@tentpiglet I think my solution might (temporarily) help you out with the DNS issues you and others in this topic are experiencing. 1,5 weeks of stable connection so far.

Gertjan

@mikymike82 said in Slow DNS after 22.05:

my dns resolution was a complete mess

What about answering questions ?

Btw : I used a bare bone system (old Dell desktop, added a Quad Intel NIC) for nearly 10 years.
Since last Juin I'm using a SG 4100. Works great.
I have DNS statistics.

@jax said in Slow DNS after 22.05:

why so many users experienced the same phenomenon

120 thousand plus active users - all without DNS ?
That is, I can tell that my DNS works. edit : showing another way to see the resolver restarting.

@mikymike82 said in Slow DNS after 22.05:

22.01 no problems and after upgrading to 22.05

If you don't use IPv6, do what @johnpoz said.

Btw : I never used 22.01 - 22.01 was pre installed on my 4100, but I upgraded the day I received the unit.

johnpoz

@jax said in Slow DNS after 22.05:

We've all experienced

We are??? I am not having any issues..

why so many users experienced the same phenomenon.

So many users? like the handful posted here? Where are these users posting that they are having issues? The 1000's and 1000's of them that are running 22.05? All having issues? Some how I have seem to have missed that it was such a wide spread problem - very odd since I am on the board like all day pretty much every day.. And some how I have missed that its everyone having the issue..

provels

FWIW, I have had no problems on the VM and package set in my sig, clean built 2.6>22.01>22.05. I use IPv4/v6.

johnpoz

@provels But how can that be - we clearly all having issues, maybe your having an issue and just don't know it ;) hehehehe

Kempain

Managed to capture some nslookups when DNS bombed out.
It's really tricky to troubleshoot because it happens sporadically and randomly.

Interestingly requests to pfSense timed out twice, then it only returned an IPv6 address without IPv4, then it returned both IPv6 and IPv4. Maybe this adds some credence to the issue being related to IPv6 but who knows. IPv6 was returned first in this particular case so disabling IPv6 would have likely caused more harm.

I still want to check the unbound service to see how often that is restarting which I'll try do later to see if those 2 events line up.

pfSense DNS issue.png

johnpoz

@kempain said in Slow DNS after 22.05:

I still want to check the unbound service to see how often that is restarting which I'll try do later to see if those 2 events line up.

Also simple enough to just see how long its been running..

[22.05-RELEASE][admin@sg4860.local.lan]/root: unbound-control -c /var/unbound/unbound.conf status
version: 1.15.0
verbosity: 1
threads: 4
modules: 2 [ validator iterator ]
uptime: 333105 seconds
options: control(ssl)
unbound (pid 13952) is running...
[22.05-RELEASE][admin@sg4860.local.lan]/root:

So mine has been up 333K seconds, or getting close to 4 days.. Last time I posted it was like 10 days, another 6 days. I tend to restart it when doing something for some thread, where they need an option or something - think last one someone was asking how to block youtube, etc.

But you have no purposely restarted unbound/pfsense and your status shows that its only been up a short amount of time - something is wrong.

Kempain

Cheers @johnpoz

So looks like mine is restarting relatively regularly.

Cool_Corona

Unbound on 2.5.2

johnpoz

@cool_corona @Kempain 300 some seconds unbound being up, doesn't bode well for caching name server ;)

Cool_Corona

@johnpoz How to track all unbound restarts?

tentpiglet

@johnpoz said in Slow DNS after 22.05:

Do you have IPv6?

No. Although I think pfSense assigns a link local address to my wan and lan interface, my ISP does not provide me with a ip6 address.

@gertjan said in Slow DNS after 22.05:

22.05 or 2.6.0 ?

22.05-RELEASE (amd64)
built on Wed Jun 22 18:56:13 UTC 2022
FreeBSD 12.3-STABLE

UNstable means :
You found it 'not running', and no process 'unbound' was present when you list processes ?
Or the process unbound was there, but didn't answer ?
An nslookup from a PC on a LAN failed ?

unstable means I'm using a browser on a client and I get a "DNS_PROBE_FINISHED_NXDOMAIN" error (google chome), and when I hit the reload button a few moments later, the page will be found.

edit : how many times a day unbound restarts ?

grep 'start of service' /var/log/resolver.log | wc -l

64

first entry was at 10:21am local time this morning, so that's over the past 2 hours.

johnpoz

@tentpiglet said in Slow DNS after 22.05:

DNS_PROBE_FINISHED_NXDOMAIN

And what specific were you looking for - NX is not a dns failure, that is what you were looking for doesn't exist.

Also - browser errors are not troubleshooting dns problem - for all we know your browser is using doh and has zero to do with yoru local dns.

tentpiglet

@johnpoz said in Slow DNS after 22.05:

And what specific were you looking for - NX is not a dns failure, that is what you were looking for doesn't exist.

Randomly, any site I would go to. For example, the last time it happened when I said "enough is enough" and spun up a pihole container on my Proxmox server, it was "www.facebook.com".

I'm pretty sure www.facebook.com exists.

My wife was also reporting random disconnects from an online game she was playing, as well as getting similar site not found errors on her phone while reading reddit. Since moving DNS over to the pihole container, she's experienced no further issues.