[MC-31848] Minecraft disrespects/overwrites java.net.preferIPv4Stack

When setting -Djava.net.preferIPv4Stack=false in Minecraft 1.6.4 and trying to connect to a ipv6 address, it fails to connect due to 'Protocol family unavailable'

passing the same option, it works fine in Minecraft 1.6.2.

Linked issues

duplicates 1

MC-3776 IPv6 Does Not Work Resolved

Comments 3

Guybrush Threepwood 2013-09-20T11:05:44Z

why do you have to overwrite it?!
take a look in the calendar: it's 2013, not 2005.

Referring to Grum's comment : Why don't you just make the Launcher IPv4-only for the time being, and add the fallback code to the client?

Anyways, please don't overwrite 'java.net.preferIPv4Stack'

Ezekiel 2013-11-27T21:06:25Z

Is this still a concern in the latest Minecraft version 13w48b? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Ezekiel 2014-01-14T18:05:25Z

Is this still a concern in the current Minecraft version 1.7.4 / Launcher version 1.3.8 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.