It seems it wasn't the issue. Even with dnsmasq killed, and the port being occupied by pihole-FTL, it still fails finding the host's ip address.
[i] Default IPv4 gateway: 192.168.0.1
Pinging 192.168.0.1...
ping: Warning: source address might be selected on device other than .
ping: unknown iface
[✗] Gateway did not respond. (Why is a default gateway important for Pi-hole?)
but gateway IS reachable:
phablet@ubuntu-phablet:~$ ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data.
64 bytes from 192.168.0.1: icmp_seq=1 ttl=64 time=3.19 ms
another errors:
*** [ DIAGNOSING ]: Networking
Device "" does not exist.
[✗] No IPv4 address(es) found on the interface.
Error: no such table: vw_gravity
dig: '' is not a legal name (unexpected end of input)
[✗] Failed to resolve via localhost (127.0.0.1)
dig: couldn't get address for '': not found
[✗] Failed to resolve via Pi-hole ()
Well, for what it seems, pihole has a problem accessing .db files and running queries, and cannot get the ip that was given in config, or the network interface. Everything on /etc/pihole is owned by pihole user, not likely a permission issue.
also the log says pihole-ftl daemon is inactive, but is actually running:
phablet@ubuntu-phablet:~$ sudo service pihole-FTL status
[ ok ] pihole-FTL is running
The admin page works, but almost anything related to db queries fails, including DNS filtering itself. It has no issues working as a DNS server, but filtering and blocking won't work (since it cannot access blacklisted hostnames).
Also, the amount of domains on blacklist on web interface is "-2", and I dunno how that's possible.