On Thursday 23 of June 2016 02:42:23 Mike Bird wrote:
> Repeatable proxy 502 errors during apt-get update, e.g.:
>
> W: Failed to fetch
> http://ppa.quickbuild.pearsoncomputing.net/trinity/trinity-r14.0.0/ubuntu/d
>ists/jessie/main/binary-i386/Packages 502  Proxy Error
>
> Appears to be due to no DNS A record for:
>   ppa2.quickbuild.raptorengineering.com
>
> FWIW there is an A record for the above if "2" omitted.
>
> --Mike
>

By the way, for the apt sources you can use a redirector on the mirror - host 
mirror.ppa.trinitydesktop.org, rest url is unchanged. This should cover the 
changes that have apparently now underway on the primary site.

-- 
Slávek