I've used it for some time, it feels very much like it is in maintenance mode.
You manage a PKI and have to distribute the keys yourself, no auth/login etc.
it's much better than wireguard, not requiring O(N) config changes to add a node, and allowing peoxy nodes etc.
iirc key revocation and so on are not easy.
Nebula just had a major release that added IPv6 support for overlay networks. Hardly maintenance mode.
The main company working on it now seems to be adding all the fancy easy-to-use features as a layer on top of Nebula that they are selling. I personally appreciate getting to use the simple core of Nebula as open source. It seems very Unix-y to me: a simple tool that does one thing and does it well.
Nebula does not require O(n) config changes for adding a node.
O(n) is only required for:
- active revocation of a certificate (requires adding the CA fingerprint to the config file)
- adding/removing a lighthouses (hub for publishing IPs for p2p) or relay (for going over p2p)
- CA rotation
This problem has been brought up in the OpenZiti community many times. I like Nebula, but it's not 'truly open source'.