Example: Deploying unikernels using Albatross on NixOS

A very simple server is defined in configuration.nix. It imports the module exposed by Albatross and enable it. The Albatross package and module are imported in flake.nix.

The TLS endpoint is enabled and ports 8080 and 4433 are forwarded to the unikernels.

The TLS endpoint accepts commands from the internet to deploy or kill unikernels. It needs server.pem and server.key to authenticate to clients and cacert.pem to authenticate clients. The client needs ca_key.key and cacert.pem. Examples of public and private keys are already present in the repository, you can generate new keys using:

nix shell github:Julow/albatross -c albatross-client generate ca_key ca_db

Build a VM running the example configuration:

nixos-rebuild build-vm --flake ".#test"

And run it:

QEMU_NET_OPTS="hostfwd=tcp::1025-:1025,hostfwd=tcp::2222-:22,hostfwd=tcp::8080-:8080,hostfwd=tcp::4433-:4433" QEMU_OPTS="-display none" ./result/bin/run-nixos-vm

Albatross should be running and can be controled on port 1025 using albatross-client-bistro.

Download the latest version of https.hvt from https://builds.robur.coop/job/static-website and deploy it:

curl -LO https://builds.robur.coop/job/static-website/build/latest/f/bin/https.hvt

nix shell github:Julow/albatross -c albatross-client create --force \
  --ca=./cacert.pem --ca-key=./ca_key.key --server-ca=./cacert.pem \
  --net=service --arg="--ipv4-gateway=10.0.0.1" \
  --arg="--ipv4=10.0.0.2/24" \
  https ./https.hvt

The --ca, --ca-key and --server-ca arguments specify the keys, --net=service --arg="--ipv4-gateway=..." allows the unikernel to access the internal network and --arg="--ipv4=..." assign a local IP address to the unikernel.

You should see:

host [vm: :https]: success: created VM

The logs can be viewed with:

nix shell github:Julow/albatross -c albatross-client console https \
  --ca=./cacert.pem --ca-key=./ca_key.key --server-ca=./cacert.pem

The http server should be accessible from the host system:

curl -k https://localhost:4433