dns probe started

[Ana_Gonzalez]

Actual Behaviour:

I'm using Pihole in Raspberry pi 4 mode B 8GB RAM since +6 months no issues. (More than ~$2.4million total queries +8 clients uptime +60days)

PROBLEM:

Since few weeks I think something is wrong resolving the queries because when I'm using web browser (Chrome, Firefox, Opera) in my personals computers/laptos or smartphones I get 75% the time "dns probe started" or "DNS_PROBE_FINISHED_BAD_CONFIG" and the webpage never load, if you refresh it few times it load, sometimes you can't even watch any youtube video or play any games because you don't have internet connection at all. Since few weeks it has gotten worse and worse until today in my computer and smarthphone could not connect to Internet.

I know something is wrong with pihole and not my ISP, because I just turn off pihole and use ISP DNS and everything works fine as espected. Sometimes I saw in queries logs "Reply N/A" or "Reply 170ms"
That's why I think something is wrong resolving the queries. As I said ~75% times pihole fails and sometimes it works perfectly fine. I rebooted my sistem and pihole services few times, my sistem is up to day "0 packs need to be upgraded"

i see in pihole -t real time queries being forward ok, but I see a lot of traffic, maybe my sistem could not handle that? My cpu is working at 5% all the time, 7gb free of ram and i did not have a issue like this before in +6 months with same volumen of traffic.

I've spent a lot lot lot of hours trying some stuff to fix this before asking for help, and I readed lot of documentation from pihole but I don't find the answer to this problem.

Thank you so much for help me, I appreciate it!

Debug Token:

https://tricorder.pi-hole.net/FxUpkzCD/

I had to ran 4 times pihole -d until I could upload it

[Ana_Gonzalez]

I just took all these captures at the same time 5 minutes ago

[jfb]

Let's take a look at the query volume. Please post the outputs of the following commands from the Pi terminal - you can paste the output into a reply.

echo ">stats >quit" | nc localhost 4711

echo ">top-clients withzero (15) >quit" | nc localhost 4711

echo ">top-domains >quit" | nc localhost 4711

echo ">top-ads >quit" | nc localhost 4711

ls -lha /var/log/pihole.log*

ls -lha /etc/pihole/pihole-FTL.db

[Ana_Gonzalez]

@jfb

echo ">stats >quit" | nc localhost 4711

@jfb

echo ">top-clients withzero (15) >quit" | nc localhost 4711

@jfb

echo ">top-domains >quit" | nc localhost 4711

@jfb

echo ">top-ads >quit" | nc localhost 4711

@jfb

ls -lha /var/log/pihole.log*

@jfb

ls -lha /etc/pihole/pihole-FTL.db

[jfb]

There is nothing out of the ordinary in these outputs. This is a relatviely low query volume and nothing that should impact the performance of the Pi.

Let's take a look at some of the replies in the dnsmasq log:

grep reply /var/log/pihole.log | tail -n25

[Ana_Gonzalez]

@jfb

grep reply /var/log/pihole.log | tail -n25

[jfb]

The SERVFAIL messages indicate your upstream DNS server did not resolve the query that was sent to it.

[Ana_Gonzalez]

My upstream DNS is 1.1.1.1 and 1.0.0.1.

Should I add more upstream DNS servers here?

[jfb]

I would start by changing the upstream servers to one of the other choices. See if this clears the errors.

[Ana_Gonzalez]

I already tried it. I swapped it to OpenDNS ipv4/ipv6 for few days ago and the results where the same, I even used 4 DNS OpenDNS and Cloudflare ipv/ipv6 and the problem still.

[Ana_Gonzalez]

Yep, still same error. I swapped it again

[Ana_Gonzalez]

I still having the same issue, there's something else that I can do to fix it?