Local package cache setup
Opensuse: uses squid.
/etc/sysconfig/proxy
PROXY_ENABLED="yes"
HTTP_PROXY="http://192.168.1.118:3128/"
Ubuntu: uses apt-cacher-ng.
/etc/apt/apt.conf.d/02proxy
Acquire::http { Proxy "http://fileserv:3142"; };
Arch: uses nginx.
/etc/pacman.d/mirrorlist
Server = http://fileserv:8080/archlinux/$repo/os/$arch