Adding a subnet router with subnet that is in 100.x CIDR range

SUPPORT QUESTIONS
1

Tailscale version v1.36.0
Your operating system & version. Linux - docker image

Hi all,
I am trying to add a subnet router (running in Kubernetes), however the subnet has 100.64.0.0/12 CIDR. I was wondering if this will be a problem since Tailscale also has 100.x.y.z range and if there is anyway around this problem.

Thank you

1 Like
2

Adding a little more context.
I tried disabling IPv4 and still was not able to route 100.64.0.0/12 subnet (making sure that this CIDR is enabled on the subnet router in the admin console).

I see these logs in the router when ipv4 is enabled and trying to hit 100.65.244.250 private ip:

2023/02/11 08:30:26 Accept: TCP{100.74.xxx.yy:57585 > 100.65.244.250:8080} 64 tcp ok
2023/02/11 08:30:26 netstack: could not connect to local server at 127.0.0.1:8080: dial tcp 127.0.0.1:8080: connect: connection refused

and when IPv4 is disabled I do not see any logs.

Running a traceroute when ipv4 is disabled shows that Tailscale is not resolving the IP and it is going through normal resolution and hitting the internet. I should also mention that I am on a MacOS client.