pyrox.dev
1<section xmlns="http://docbook.org/ns/docbook"
2 xmlns:xlink="http://www.w3.org/1999/xlink"
3 xmlns:xi="http://www.w3.org/2001/XInclude"
4 version="5.0"
5 xml:id="sec-nix-network-issues">
6
7<title>Network Problems</title>
8
9<para>Nix uses a so-called <emphasis>binary cache</emphasis> to
10optimise building a package from source into downloading it as a
11pre-built binary. That is, whenever a command like
12<command>nixos-rebuild</command> needs a path in the Nix store, Nix
13will try to download that path from the Internet rather than build it
14from source. The default binary cache is
15<uri>https://cache.nixos.org/</uri>. If this cache is unreachable,
16Nix operations may take a long time due to HTTP connection timeouts.
17You can disable the use of the binary cache by adding <option>--option
18use-binary-caches false</option>, e.g.
19
20<screen>
21# nixos-rebuild switch --option use-binary-caches false
22</screen>
23
24If you have an alternative binary cache at your disposal, you can use
25it instead:
26
27<screen>
28# nixos-rebuild switch --option binary-caches http://my-cache.example.org/
29</screen>
30
31</para>
32
33</section>