- DNS SRV record support in apt
- Apt supports a subset of the DNS SRV server records protocol as
- described in [RFC 2782](https://tools.ietf.org/html/rfc2782) for service discovery.
- Before connecting to the requested server APT will send a SRV
- record request of the form `_$protocol._tcp._$host`, e.g.
- `_http._tcp.ftp.debian.org` or `_http._tcp.security.debian.org`.
- If the server sends SRV records
- as a reply APT will use those to connect to the server(s) in
- this reply. It will honor the `priority` field in the reply.
- However it does not implement the `weight` algorithm as described
- in RFC 2782. It will use an equal weight for each server of the
- same priority.
- If connecting to a server fails APT will retry with the next one
- and remove the server from the list of valid servers for this