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Comment by LoganDark

1 day ago

Last I read the docs while troubleshooting this very problem, you cannot specify node names as the source or destination of a grant. You can specify direct IP address ranges, node groups (including autogenerated ones) or tags, but not names.

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

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LoganDark

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ghthor  1 day ago

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

  • andrew-d  1 day ago

    Hi there, I work at Tailscale.

    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"],
    },
  ]