dns

Documentation

Index

• type Server
  • func New(o *orchestrator.Orchestrator) *Server
  • func (d *Server) Start(port uint64) error
  • func (d *Server) Stop() error

Types

type Server

type Server struct {
	*orchestrator.Orchestrator
}

func New

func New(o *orchestrator.Orchestrator) *Server

New creates a new DNS service. The service helps applications find out the IP addresses of other satellites. It uses the custom (made up) "celestial." TLD. A satellite DNS record has the form [ID].[SHELL].celestial, where [ID] is the identifier and [SHELL] is the index of the shell of the satellite. That maps to an IP address. Additionally, ground station IP addresses can be determined with [NAME].gst.celestial, where NAME is the ground station name. Our DNS server supports only queries, only UDP (no DNSSEC), and only A records. This service relies on configuring systemd-resolved to use our DNS server for the celestial TLD.

func (*Server) Start

func (d *Server) Start(port uint64) error

Start starts our DNS service. We first check if systemd-resolved is available and panic otherwise. We then place a configuration file in /etc/systemd/resolved.conf.d/celestial.conf that contains the following:

```conf [Resolve] DNS=127.0.0.1:[port] Domains=~celestial DNSStubListener=no DNSStubListenerExtra=0.0.0.0:53 ```

We then restart systemd-resolved.

func (*Server) Stop

func (d *Server) Stop() error

Stop stops our DNS service. We remove the configuration file we placed in /etc/systemd/resolved.conf.d/celestial.conf and restart systemd-resolved.