Could not access admin panel, no error message

[meadows]

The issue I am facing:
Could not access the admin panel

Details about my system:
Debian 11 using Openmediavault Version 6.
Fritzbox Router cable 6690
first pihole ip 192.168.1.15 (this one works like a charm)
second ip 192.168.1.30 (this one has no admin access, but pihole -c works)
both with OMV 6

What I have changed since installing Pi-hole:
I tried pihole -r w/o success, than pihole uninstall and reinstalled it via curl -sSL https://install.pi-hole.net | bash

The debug log pihole -d looks fine to so far, I am missing an error message and would appreciate to be pointed in the right direction.

The debug token is: https://tricorder.pi-hole.net/HHGyTTYu/

[rdwebdesign]

This is expected.
You have installed Pi-hole without the web server (lighttpd) and without the web interface (admin panel):

*** [ DIAGNOSING ]: lighttpd version
[✗] lighttpd version could not be detected.

and:

*** [ DIAGNOSING ]: Setup variables
    ...
    INSTALL_WEB_SERVER=false
    INSTALL_WEB_INTERFACE=false

[meadows]

OK, you are right. I initiated pihole -r again and selected the lighttp web server and the web interface. The debug log of pihole -d did not change. Lighttpd is installed. systemctl status lighttpd -> is active.

The debug token is: https://tricorder.pi-hole.net/bM7Bj5NP/

[rdwebdesign]

I read both logs again.
Actually, lighttpd is running and using port 80 (it was running on the previous debug log, too).

[✓] tcp:0.0.0.0:80 is in use by lighttpd

But both logs show the web interface is disabled:

*** [ DIAGNOSING ]: Web version
[i] Web: Disabled in setupVars.conf via INSTALL_WEB_INTERFACE=false

What is the output of ls -la /var/www/html/admin ?

[meadows]

root@cloud:/home/omv# ls -la /var/www/html/admin
total 596
drwxr-xr-x 7 root root 4096 Sep 12 19:04 .
drwxrwxr-x 3 www-data www-data 4096 Sep 12 19:04 ..
-rw-r--r-- 1 root root 8 Sep 12 19:04 .codespellignore
-rw-r--r-- 1 root root 577 Sep 12 19:04 .editorconfig
drwxr-xr-x 8 root root 4096 Sep 12 19:13 .git
-rw-r--r-- 1 root root 12 Sep 12 19:04 .gitattributes
drwxr-xr-x 3 root root 4096 Sep 12 19:04 .github
-rw-r--r-- 1 root root 194 Sep 12 19:04 .gitignore
-rw-r--r-- 1 root root 824 Sep 12 19:04 .php-cs-fixer.dist.php
-rw-r--r-- 1 root root 133 Sep 12 19:04 .stickler.yml
-rw-r--r-- 1 root root 56 Sep 12 19:04 .yamllint.conf
-rw-r--r-- 1 root root 2336 Sep 12 19:04 CONTRIBUTING.md
-rw-r--r-- 1 root root 14163 Sep 12 19:04 LICENSE
-rw-r--r-- 1 root root 9226 Sep 12 19:04 README.md
-rw-r--r-- 1 root root 6320 Sep 12 19:04 api.php
-rw-r--r-- 1 root root 15125 Sep 12 19:04 api_FTL.php
-rw-r--r-- 1 root root 15490 Sep 12 19:04 api_db.php
-rw-r--r-- 1 root root 2630 Sep 12 19:04 auditlog.php
-rw-r--r-- 1 root root 3990 Sep 12 19:04 cname_records.php
-rw-r--r-- 1 root root 354 Sep 12 19:04 composer.json
-rw-r--r-- 1 root root 2825 Sep 12 19:04 composer.lock
-rw-r--r-- 1 root root 2677 Sep 12 19:04 db_graph.php
-rw-r--r-- 1 root root 5003 Sep 12 19:04 db_lists.php
-rw-r--r-- 1 root root 9891 Sep 12 19:04 db_queries.php
-rw-r--r-- 1 root root 1668 Sep 12 19:04 debug.php
-rw-r--r-- 1 root root 3589 Sep 12 19:04 dns_records.php
-rw-r--r-- 1 root root 1352 Sep 12 19:04 gravity.php
-rw-r--r-- 1 root root 3722 Sep 12 19:04 groups-adlists.php
-rw-r--r-- 1 root root 4526 Sep 12 19:04 groups-clients.php
-rw-r--r-- 1 root root 7978 Sep 12 19:04 groups-domains.php
-rw-r--r-- 1 root root 3289 Sep 12 19:04 groups.php
drwxr-xr-x 3 root root 4096 Sep 12 19:04 img
-rw-r--r-- 1 root root 10162 Sep 12 19:04 index.php
-rw-r--r-- 1 root root 5394 Sep 12 19:04 login.php
-rw-r--r-- 1 root root 369 Sep 12 19:04 logout.php
-rw-r--r-- 1 root root 1809 Sep 12 19:04 messages.php
-rw-r--r-- 1 root root 2960 Sep 12 19:04 network.php
-rw-r--r-- 1 root root 233148 Sep 12 19:04 package-lock.json
-rw-r--r-- 1 root root 2957 Sep 12 19:04 package.json
-rw-r--r-- 1 root root 116 Sep 12 19:04 phpstan.neon.dist
-rw-r--r-- 1 root root 6924 Sep 12 19:04 queries.php
-rw-r--r-- 1 root root 2035 Sep 12 19:04 queryads.php
drwxr-xr-x 4 root root 4096 Sep 12 19:04 scripts
-rw-r--r-- 1 root root 105697 Sep 12 19:04 settings.php
drwxr-xr-x 4 root root 4096 Sep 12 19:04 style
-rw-r--r-- 1 root root 950 Sep 12 19:04 taillog-FTL.php
-rw-r--r-- 1 root root 949 Sep 12 19:04 taillog.php

[meadows]

OK - I assume that it is not a pihole configuration point, rather than an nginx configuration issue.
To verify it I run:

pihole uninstall

sudo rm -rf /etc/.pihole /etc/pihole /opt/pihole /usr/bin/pihole-FTL /usr/local/bin/pihole /var/www/html/admin

curl -sSL https://install.pi-hole.net | bash

So far - still no access to the WEB interface using lighttp.

The solution was to reconfigure nginx according to the openmediavault salt environment.

sudo omv-salt stage run deploy

reconfigured nginx and I am able to access the WEB interface via lighttp.

Thank you very much for your help, as you directed me to the point excluding the pihole configuration during troubleshooting.