[RFR]: 8222562: IPv6 only systems fail on setsockopt(IPV6_V6ONLY, 0)

[Chris Hegarty]

Arthur,

On 16/04/2019 22:34, Arthur Eubanks wrote:
> Hi,
> 
> Copied from the bug https://bugs.openjdk.java.net/browse/JDK-8222562:
> Some of the networking code tries to support dual socket support. 
> However, it doesn't work with IPv6 only systems.
> 
> setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, 0) returns a failure with 
> errno EAFNOSUPPORT, and then the networking code bails. It should not 
> bail when it sees that trying to set IPV6_V6ONLY fails.

I assume that you are on Linux, right? If so, have you compiled the
Kernel without IPv4 support? How have you configured your system without
IPv4 support?

I'm curious as I would like to try something similar, as well as on
other platforms, macOS, etc.

-Chris.