[Starlink] starlink and VPN

[Gert Doering]

Hi,

On Mon, Jan 20, 2025 at 11:25:04PM -0800, David Lang via Starlink wrote:
> the logs on the client are reporting link local: (not bound) when trying
> UDP, when I try TCP (and clamp the mtu low) I can connect from the starlink
> side (st least sometimes) but cannot get the routing the other way to work

If the VPN comes up (both sides declare TLS handshake success, you see
the PUSH_REPLY messages on both sides), with TCP, it "should just work"
- if not, it's not a starlink issue but something in the OpenVPN setup,
or just a plain "ipv4_forward=1" missing on the server side...

Feel free to unicast me your OpenVPN logs (verb 3) if needed.

With UDP, "it should also work just fine", but MTU might interfere - and
of course UDP rate limiting.  Try "openvpn --max-packet-size 1000" or 
even lower, if it's really MTU related (tcpdump on both ends on the outside
interface should show if packets are getting lost).

Gert Doering
        -- openvpn upstream
-- 
have you enabled IPv6 on something today...?

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