Re: Progress on tailscale on NetBSD (plus $ available)

[David Young <dyoung%netbsd.org@localhost>]

On Thu, Mar 05, 2026 at 04:45:58PM +0000, David Brownlee wrote:
> I have some potential progress on tailscale working on NetBSD
> 
> I created a Freelancer.com project for "Fix Tailscale tun networking
> on NetBSD" with a small amount of $ for "have a look and document what
> you tried" and somewhat more for "get it working". While @vudinhgiang
> did not get it fully working, they found enough of interest that they
> were paid the full amount :)
> 
> Anyway, back to the progress.
> 
> This is based on the wip/tailscale package, which is v1.94.2
> 
> The status quo is: rc.d/tailscaled has "-tun userspace-networking",
> which has tailscale working with (unsurprisingly) userspace
> networking, changing it to "-tun tun0" will cause tailscale to try to
> start tun networking and fail.
> 
> @vudinhgiang discovered that if you manually set the IP address on
> tun0, the tailscale network comes up. As a proof of concept he hacked
> in some code inside tailscale to shell out to ifconfig to set the IP,
> but it also works if you manually set the IP before {re,}starting
> tailscaled
> 
> I don't know what is special about tailscale and NetBSD, as tailscale
> runs fine on other BSDs and wireguard runs fine on NetBSD, but maybe
> someone with more tun knowledge has an idea?
> 
> Once the tun networking has started we still cannot contact other
> systems as the NetBSD end appears to use its main IP address, not the
> IP of the tun interface

Does the default route use the Tailscale tunnel or some other interface?
What about the route to the Tailscale subnet?  Do you mind sharing
`netstat -rn -f inet`?

When I struggled with NetBSD choosing the wrong IP source address, many
years ago, I developed `options IPSELSRC`.  When that's enabled, you can
alter the source-address selection policy using a per-interface sysctl.
You probably do not need to resort to that but it's there if you need
it.

David

-- 
David Young
dyoung%pobox.com@localhost