Keenetic supports ZeroTier out of the box, but Tailscale has to be set up through the console.

First, you need to set up Opkg.

Documentation:

Notes:

  • Keenetic doesn’t like it when other applications change routes or DNS, so we’ll disable that.
  • Routes are needed — you can add them through Keenetic itself or use the scripts from the links above.
  • --netfilter-mode=off --accept-dns=false — the secret to making it work reliably
  • An exit node (--advertise-exit-node) is also best avoided, though this doesn’t prevent routing manually in the same way (all machines are on the same network anyway, and the routers are already configured to route outward)
  • The machine name defaults to the hostname, but it can also be changed separately.

Installation

opkg install tailscale ip-full
/opt/etc/init.d/S06tailscaled start

tailscale up --login-server=https://... --authkey hskey-auth-... --netfilter-mode=off --accept-dns=false
tailscale set --advertise-routes 192.168.1.0/24

ip route show table all

If you want to expose the whole subnet, you need to approve routing to it in the network admin panel.