You can ack based on groups, and you can out users into groups. So if you auth a node, it’s now your node and the ACL for your user / group will apply.
But yes I don’t think you can ACL based o the hostname
But yes I don’t think you can ACL based o the hostname
Part of the reason that we don't (currently) let you do this is that a hostname is a user-reported field, and can change over time; it's not a durable form of identity that you can write ACLs on. One could imagine, for example:
1. Creating an ACL rule that allows hostname "webserver" to hostname "db".
2. (time passes)
3. Hostname "webserver" is deleted/changed to "web"/etc.
4. Someone can now register a user device with the system hostname set to "webserver"
Should they be allowed to inherit the pre-existing ACL rule?
However, you can accomplish something very close to what you're asking for, I think, by defining a "host" in the policy file (https://tailscale.com/docs/reference/syntax/policy-file#host...) that points to a single Tailscale IP. Since we don't allow non-admins to change their Tailscale IP, this uniquely identifies a single device even if the hostname changes, and thus you can write a policy similar to:
"hosts": {
"myhost": "100.64.1.2",
},
"grants": [
{
"src": ["myhost"],
"dst": ["tag:db"],
},
]Tags are just a better way to do this for tailscale only nodes, as now the ACL doesn’t require any change during a device key rotation.