I installed pihole by cloning from git and running the basic-install script. After following the prompts, the install finished, and immediately I had no internet access on my ubuntu box. After rebooting, I still had no internet access. So I ran the uninstall script. I still had no internet access. I rebooted again. Still no access.
I manually edited /etc/resolv.conf (which read 127.0.0.1) to 8.8.8.8, and access was restored. I tried running the install script again. This time, the install finished, and I still had internet access.
I navigated to /admin, and the dashboard says "DNS service not running (red circle) .
Pi-hole is designed to be run with lighttpd and it appears that you are using Apache. That will cause various issues with the web interface not working correctly.
The debug log also shows numerous issues with your IP networking. You should review the local copy of the log and correct those issues.
If running apache is a problem for a pi-hole installation, that should be mentioned in the prerequisites section of the documentation.
I did not have any issues with my IP networking before installing pi-hole. I would like to undo whatever changes were made to my networking. Running the uninstall script does not do this, apparently. So I'd like to know how I can do it manually.
If you have another Web server already running, such as Apache, Pi-hole's Web server will not work. You can either disable the other Web server or change the port on which lighttpd listens, which allows you keep both Web servers running.
Pi-hole comes with dhcpcd5 for network settings and applying them:
pi@noads:~ $ apt show dhcpcd5
[..]
Description: DHCPv4, IPv6RA and DHCPv6 client with IPv4LL support
dhcpcd is a one stop network management daemon which includes
* RFC compliant DHCPv4 and DHCPv6 clients
* DHCPv6 Prefix Delegation support
* IPv4LL (aka ZeroConf) support
* ARP address conflict resolution
* Link carrier detection
* Wireless SSID profiles
* ARP ping profiles
You can check if its still installed with below one: