Apache won't start - unable to find IPv4 address of "(none)"

While not the ideal solution if you need it, disabling mod_unique_id should fix the issue at hand.

#LoadModule unique_id_module modules/mod_unique_id.so

In case anyone else encounters this, here's how I solved it on Gentoo: make sure the ServerName inside /etc/apache2/httpd.conf matches an address or an alias from your /etc/hosts file.

next thing you want to make sure is that you have these 2 lines inside /etc/host.conf:

order hosts, bind
multi on

these lines tells apache to consult /etc/hosts file thus it can find the name server there.

to fix the error, edit the /etc/hosts file and add your computer ip

127.0.0.1       localhost
192.168.0.123   {computerName}

replace {computerName} with your computer name in /etc/hostname