Re: [Tails-dev] Debian 9: Build fails consistently, name re…

Arnaud:
> While these patches don't hurt, I can tell you now that they solve
> nothing. And I don't want to be responsible for cluttering the build
> system with useless stuff like that ;)

Thanks! :)

> So at the moment, I'm still in this situation where build fails, and I
> retry and retry until at some point it succeeds. I didn't have much time
> to work on that yet. I'll come back to you when I workaround this issue,
> one way or another.

A simple workaround for when you have cached everything needed for the build (i.e. after your have successfully built *once*) is to add "offline" to the TAILS_BUILD_OPTIONS environment variable. Of course, getting to the point when you have everything cached will be painful, but at least you will be able to rebuild as much as you like without risk of network issues.

Here's a crazier idea to explore:

* run apt-cacher-ng on the host (base your configuration on vagrant/provision/assets/acng.conf)
* add "extproxy" to TAILS_BUILD_OPTIONS
* set the http_proxy environment variable to point to the host's apt-cacher-ng instance
* the "offline" option doesn't work with external proxies, but you can set Offline mode in apt-cacher-ng's configuration instead
* sadly apt-cacher-ng lacks an option for retrying failed downloads, but if you can find any other HTTP proxy that can, set that up as well and then configure apt-cacher-ng to use it as a parent proxy itself (see the `Proxy` option).

Happy hacking! Let us know if you find out something about the last point (parent proxy that retries). If it improves your situation without using much resources we probably want to add it to the VM's default apt-cacher-ng setup.

Cheers!