# Installing behind a proxy {#sec-installing-behind-proxy} To install NixOS behind a proxy, do the following before running `nixos-install`. 1. Update proxy configuration in `/mnt/etc/nixos/configuration.nix` to keep the internet accessible after reboot. ```nix networking.proxy.default = "http://user:password@proxy:port/"; networking.proxy.noProxy = "127.0.0.1,localhost,internal.domain"; ``` 1. Setup the proxy environment variables in the shell where you are running `nixos-install`. ```ShellSession # proxy_url="http://user:password@proxy:port/" # export http_proxy="$proxy_url" # export HTTP_PROXY="$proxy_url" # export https_proxy="$proxy_url" # export HTTPS_PROXY="$proxy_url" ``` ::: {.note} If you are switching networks with different proxy configurations, use the `specialisation` option in `configuration.nix` to switch proxies at runtime. Refer to [](#ch-options) for more information. :::