betterdns

We would like to register new vms to the DNS as soon as they're up & running. To randomly assign any IPs to new vms/container or use DHCP.

The goal of this project is to achieve service discovery.

Issues:

How do we unregister vms/containers that might shut down in a non-gracefully manner?
- Use health checks.
- Try to terminate non-healthy vms/containers.
- Then unregister them from the DNS.

Repository structure

Path	Description
`src/dns_manifest_parser`	Parser for dns zone manifest.
`src/dns_operator`	Operator of the dns server. Highly decoupled into 3 internal services: `controller.rs`, `runtime.rs` & `watcher.rs`.
`src/rest_api`	REST API server.

TODO: Next steps

Write tests.

Getting started

This binary will create 2 threads:

One thread serving the REST API to {create,read,update,delete} records of the dns zone manifest.
Another one will act as an operator, watching the dns zone manifest for change & updating the nameserver.
- The operator is responsible for running the nameserver as a child process.

Endpoint	Method	Description
`/`	GET	get the whole `dns` manifest
`/a`	GET	get all `A record`s.
`/a/<name>`	GET	get one `A record` by name.
`/a`	POST	create a new `A record`.
`/a/<name>`	PUT	update an `A record` by name.
`/a/<name>`	DELETE	delete an `A record` by name.

Installation

git clone https://gitlab.com/alexandre.mahdhaoui/betterdns
mv betterdns "$HOME"
"$HOME/betterdns/scripts/update.sh"

Please make sure to have a customized copy of Corefile, dns_manifest & Rocket.toml in the directory that runs betterdns.

If you want to secure your alpine with a firewall:

https://wiki.alpinelinux.org/wiki/How-To_Alpine_Wall

Considerations

We will have a problem when we will try to authenticate/authorize clients. Indeed, we'll maybe try to use JWT tokens to authenticate new VM/container trying to register to the DNS.