Change pi hole gui port on installation?

hello ,
want to know if the following is a problem:
I have a working PI3 with zoneminder server , and I want to install on it PI-hole also.
all is for home used , no more then 3 devcies connected to the internet.
cpu \ memory - I don't think sould be a problem.

the "problem' is that zonmidner is working on port 80
and also the PI-Hole
so can I install the pi-hole and tell him to use anther port for the gui interface? 8081 for example?
what will happand if I install it while the zoneminder is working ? will the installtion faild?
or only the gui will not wrok , then I will be able to change it on the config file?


This is what will happen. Pi-hole uses the webserver lighttpd - you can find everything you need in its config files.

I have install PI-hole while zoneminder is working
the installtion went without problems
I have change the port to 8080 , reboot the lighttpd service
and now pi-hole is working on port 8080 , and zoneminder on port 80


i do similar with the lighttpd server. just remember you'll need to change the port again in the config if you update pi-hole (at least for the moment).

What version of lighttpd does your system have? If it's new enough then you can do an override to update the port and not need to edit lighttpd.conf so you can avoid the update reset.

Regarding Dan's suggestion, refer to Lighttpd daemon won't start - #11 by Bucking_Horn for further details.