Você pode adicionar o seguinte a /etc/apt-cacher-ng/acng.conf
:
Proxy: http://myproxy.net:1234
Conforme descrito em este arquivo de configuração de amostra :
# The specification of another HTTP proxy which shall be used for downloads.
# It can include user name and password but see the manual for limitations.
#
# Default: uses direct connection
#
# Proxy: http://www-proxy.example.net:3128
# Proxy: https://username:[email protected]:3129