I hope this wasn't interpreted towards exe.dev. That really is a cool service!
Tags permanently erase the user identity from a device, and disable things like Taildrop. When I tried to assign a tag for ACLs, I found that I then could not remove it and had to endure a very laborous process to re-register a Tailscale device that I added to Tailscale for the express purpose of remotely accessing
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"],
},
]Could you rephrase that / elaborate on that? Isn't Tailscale's selling point precisely that they do identity-based networking?
EDIT: Never mind, now I see the sibling comment to which you also responded – I should have reloaded the page. Let's continue there!