Pihole DNS service not running, FTL offline on 5.0 beta after few days of working fine

Please follow the below template, it will help us to help you!

Please ensure that you are running the latest version of the beta code.
Run pihole -up to update to the latest, then verify that the problem still exists before reporting it.

Problem with Beta 5.0:
Web says DNS service not running, cmd line says pihole FTL offline. Tried repairing with pihole -r but didnt help. It was working fine till today but something changed since.

Debug Token:
wdpuugnsel

What is the output of these commands from the Pi teminal:

echo ">stats" | nc localhost 4711

ls -lha /etc/pihole/*.db

pi@pi3zw:~ $ echo ">stats" | nc localhost 4711
domains_being_blocked 4042782
dns_queries_today 1762
ads_blocked_today 202
ads_percentage_today 11.464245
unique_domains 197
queries_forwarded 1274
queries_cached 286
clients_ever_seen 6
unique_clients 6
dns_queries_all_types 1849
reply_NODATA 40
reply_NXDOMAIN 111
reply_CNAME 89
reply_IP 192
privacy_level 0
status enabled
---EOM---
pi@pi3zw:~ $ ls -lha /etc/pihole/*.db
-rw-rw-r-- 1 pihole pihole 375M Jan 27 00:56 /etc/pihole/gravity.db
-rw-r--r-- 1 pihole pihole 2.3M Jan 24 07:45 /etc/pihole/macvendor.db
-rw-r--r-- 1 pihole pihole 128K Jan 27 04:02 /etc/pihole/pihole-FTL.db

You have what appears to be a Pi Zero which would have 512 MB of RAM. You have over 4 million domains on blocklists, which is likely exceeding the capacity of the Pi.

As you run the Pi, the memory needs increase to respond to DNS queries received and processed. At some point, I think you are running out of memory and FTL is crashing.

You can look in /var/log/pihole.log (and previous days logs with similar names) and /var/log/syslog for any details that might support a lack of memory.

Just curious - is there a particular reason you are running 78 blocklists totalling over 4 million blocked domains?

prior to 5.0 versions, the RAM used to fill up to 380 out of 480 MB as pihole is loaded. Since 5.0 and the shift to DB for gravity, the ram is steady at 90 MB at all times.
FTL crashing never happened in the past, even with 80k queries in few hrs...

4M domains is of no particular reason, just loaded it for the sake of it but it's the same list that has been steady around 3.8 - 4 M for the past 1 yr or so. FTL crashing is new news.

To your point about memory overload and crashing, i noticed it in google cloud free tier and had to limit the domains to 1.6M , but in the pi zero even 4M never posed a problem in the versions prior to 5.0
Hope it makes sense somehow.

A good troubleshooting step might be to activate shared memory debug mode in /etc/phole/pihole-FTL.conf

https://docs.pi-hole.net/ftldns/configfile/

thank you, have enable it and let's see if it can provide some clues.

Can you pls. help with the 'DNS service not running' error in the web page. Perhaps it's the same issue!

Here is what i have, even after a fresh reboot.
'pihole status
[โœ—] DNS service is NOT running
'

same at me after 2 days. Nothing helps.

We invested a lot of effort into reducing the memory footprint of FTL. You see the result of this work :slight_smile:

What is not entirely clear is: Is FTL really offline (DNS resolution does also not work) or is it only an issue with web/CLI pretending it would be offline although it isn't?
If it is really offline, please check both /var/log/pihole.log and, maybe more important, /var/log/pihole-FTL.log for mentioning of errors or crashes.

1 Like

I just looked over your debug token on another issue. Your networking is not right. You have Pi-hole configured for the 192.168.2.0/24 network and all of your clients are on 192.168.3.0/24.

1 Like

Thank you very much, fat finger syndrome...
Surprising that DNS blocking and DHCP works well

I agree, especially with no IP addresses being found on the interface. (May be a debugger issue though.)

*** [ DIAGNOSING ]: Networking
[โœ—] No IPv4 address(es) found on the enp3s0 interface.
[โœ—] No IPv6 address(es) found on the enp3s0 interface.

that's the build in AI to cover the stupid HI (Human Intelligence)
:grin:

Did a pihole -r and got the below msgs while repairing..
Hope this shows clearly what's happening.
'
[i] Target: block-the-eu-cookie-shit-list/filterlist.txt at 120598ae2ad720431a72007ee76a1f25660b9c7c ยท r4vi/block-the-eu-cookie-shit-list ยท GitHub
[โœ“] Status: Retrieval successful

[โœ“] Storing downloaded domains in new gravity database
[โœ“] Building tree
[โœ“] Swapping databases
[โœ—] pihole-FTL: no process found
[i] Number of gravity domains: 2679488 (1931481 unique domains)
[i] Number of exact blacklisted domains: 23
[i] Number of regex blacklist filters: 68
[i] Number of exact whitelisted domains: 260
[i] Number of regex whitelist filters: 0
[โœ“] Cleaning up stray matter
[โœ“] Restarting DNS server

[โœ—] DNS service is NOT running

[i] The install log is located at: /etc/pihole/install.log
Update Complete!

Current Pi-hole version is v4.3.2-391-ge0b3405
Current AdminLTE version is v4.3.2-360-g88da85f5
Current FTL version is vDev-44b772b
'

If you're using the pi zero I think the current beta build is broken for armv61. Check /var/log/pihole-FTL.log, you'll likely see a segmentation fault at the end of the log.

still an open issue despite the recent updates in beta 5.0

"
[โœ“] Storing downloaded domains in new gravity database
[โœ“] Building tree
[โœ“] Swapping databases
[โœ—] pihole-FTL: no process found
[i] Number of gravity domains: 5726714 (4002976 unique domains)
[i] Number of exact blacklisted domains: 1
[i] Number of regex blacklist filters: 68
[i] Number of exact whitelisted domains: 251
[i] Number of regex whitelist filters: 0
[โœ“] Cleaning up stray matter
[โœ“] Restarting DNS server

[โœ“] DNS service is running
[โœ“] Pi-hole blocking is Enabled

[i] The install log is located at: /etc/pihole/install.log
Update Complete!

Current Pi-hole version is v4.3.2-397-g0a70bbd
Current AdminLTE version is v4.3.2-393-g843e46d
Current FTL version is vDev-fb01e09
pi@pi-hole:~$

"

I think you'll find they were/are different issues - the previous issue was fixed, this one is different. I would use the following thread for help for the latest version as of today - FTL crashes while using the web interface