I was not able to assign a static IP to an aliased interface using the dhcpcd5 way.
So i devised below making use of the default "source-directory /etc/network/interfaces.d" directive in the interfaces file.
This is just prove of concept/an example as I dont have ipv6 configured at home.
This test Pi only got WiFi so thats why the wlan0:0 (with ip 10.0.0.200).
Create new file:
sudo nano /etc/pihole/pihole-if
Containing below aliased interface with second IP:
auto wlan0:0
iface wlan0:0 inet static
address 10.0.0.200
netmask 255.255.255.0
Symlink it so it gets included with ifup:
sudo ln -s /etc/pihole/pihole-if /etc/network/interfaces.d/
Bring up the new interface:
sudo ifup -v wlan0:0
Reconfigure network for Pi-Hole (the second IP should appear during the wizzard):
pihole -r
Configure lighttpd to listen to the new IP address only:
sudo nano /etc/lighttpd/lighttpd.conf
Add below line:
server.bind = "10.0.0.200"
To listen only to ipv4 requests, find and hash out below line before save/close the file:
# include_shell "/usr/share/lighttpd/use-ipv6.pl " + server.port
Reload lighttpd to apply new settings:
sudo service lighttpd reload
Have dnsmasq listen to the new IP by creating below file:
sudo nano /etc/dnsmasq.d/14-pihole-if.conf
Containing:
except-interface=wlan0
except-interface=lo
listen-address=10.0.0.200
#no-dhcp-interface=wlan0
bind-interfaces
Restart dnsmasq to apply new settings:
sudo service dnsmasq restart
This is from before:
pi@raspberrypi:~ $ sudo netstat -nltup | grep 'Proto\|lighttpd\|dnsmasq\|dhcpcd\|pihole-FTL'
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:4711 0.0.0.0:* LISTEN 469/pihole-FTL
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 786/lighttpd
tcp 0 0 0.0.0.0:53 0.0.0.0:* LISTEN 8154/dnsmasq
tcp6 0 0 :::80 :::* LISTEN 786/lighttpd
tcp6 0 0 :::53 :::* LISTEN 8154/dnsmasq
udp 0 0 0.0.0.0:53 0.0.0.0:* 8154/dnsmasq
udp 0 0 0.0.0.0:67 0.0.0.0:* 8154/dnsmasq
udp 0 0 0.0.0.0:68 0.0.0.0:* 572/dhcpcd
udp6 0 0 :::53 :::* 8154/dnsmasq
And this is after:
pi@raspberrypi:~ $ sudo netstat -nltup | grep 'Proto\|lighttpd\|dnsmasq\|dhcpcd\|pihole-FTL'
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:4711 0.0.0.0:* LISTEN 530/pihole-FTL
tcp 0 0 10.0.0.200:80 0.0.0.0:* LISTEN 779/lighttpd
tcp 0 0 10.0.0.200:53 0.0.0.0:* LISTEN 1713/dnsmasq
udp 0 0 10.0.0.200:53 0.0.0.0:* 1713/dnsmasq
udp 0 0 0.0.0.0:67 0.0.0.0:* 1713/dnsmasq
udp 0 0 0.0.0.0:68 0.0.0.0:* 692/dhcpcd
The only one I was not able to bind was the dhcp service port 67.