ipv6 vs. ipv4

ipv6 vs. ipv4

[Hendrik Friedel]

Hello,

I understood that wireguard prefers ipv6 over ipv4 by default.
Nevertheless, on both Windows and Android I do not get a connection 
(only sent bytes no received bytes) when using my domain 
(friedel.dynv6.net). If I use the IP 
(2a00:6020:1bfb:c700:ba27:ebff:fe3e:6c55), I get a normal connection.
I can imagine that WG uses ipv4 (the A-record is set, I cannot change 
that, but it points to an invalid ip)

How can I -when using the domain- enforce that ipv6 is really used?

Apart from that, my suspicion is that ipv4 is in fact used here... How 
can I really find out, why I get no bytes on the received counter?

Best regards,
Hendrik

Re: ipv6 vs. ipv4

[Kilian Schauer]

17.04.2022 10:20:03 Hendrik Friedel <hendrik@friedels.name>:

> Hello,
> 
> I understood that wireguard prefers ipv6 over ipv4 by default.
> Nevertheless, on both Windows and Android I do not get a connection (only sent bytes no received bytes) when using my domain (friedel.dynv6.net). If I use the IP (2a00:6020:1bfb:c700:ba27:ebff:fe3e:6c55), I get a normal connection.
> I can imagine that WG uses ipv4 (the A-record is set, I cannot change that, but it points to an invalid ip)
> 
> How can I -when using the domain- enforce that ipv6 is really used?
> 
> Apart from that, my suspicion is that ipv4 is in fact used here... How can I really find out, why I get no bytes on the received counter?
> 
> Best regards,
> Hendrik

Hi Hendrik,

the WireGuard mobile apps prefer IPv4 for connecting to the peer, since this helps roaming between networks (where many are still IPv4-only). If the A record of the Endpoint domain is broken, it won't work.
If you want to force an IPv6 transport, you either need to put a raw IPv6 address into Endpoint, or use an AAAA-only domain.

Hope this helps,
Kilian

Re[2]: ipv6 vs. ipv4

[Hendrik Friedel]

Hello Kilian,

thanks for your reply.

>the WireGuard mobile apps prefer IPv4 for connecting to the peer, since this helps roaming between networks (where many are still IPv4-only).
understood. Is that documented somewhere? For the Windows-Client, I did 
read somewhere that ipv6 is preferred.
I find it inconsistent, that the clients behave differently.

>If you want to force an IPv6 transport, you either need to put a raw IPv6 address into Endpoint, or use an AAAA-only domain
Intuitively, I tried [my.domain.com]:51280 in order to enforce ipv6 
(just like ipv6 adresses are enclosed in [].
Would that not be an enhancement to the app?

Best regards,
Hendrik

>