vboxnetflt does not support IPv6

[Jeremy Visser]

I am using VirtualBox 2.1.0, and am networking a VM on Host Interface mode -- my eth0 interface is selected in the VM's options, effectively bridging the VM to the network on my eth0 interface.

This works for IPv4 -- ICMP, TCP, UDP, and DHCP all work beautifully, and are properly bridged to my network.

However, any attempt to use IPv6 does not work. I can confirm that router advertisements, TCP packets, and ICMP packets are not being handled by the vboxnetflt driver on my VM, and the packets are getting nowhere.

[Aleksey Ilyushin]

This is rather strange. vboxnetflt works with Ethernet frames and is not particularly concerned with what is contained in them. Can you ping host's eth0 interface from guest using eth0 link-local address? I can do it in my setup (host: ubuntu 8.04, guest: ubuntu 8.10).

What are your host and guest?

[Jeremy Visser]

Host is a fully-updated Gentoo system, and guest is Ubuntu JeOS 8.04.1. I can confirm that IPv6 works perfectly if I don't use vboxnetflt, and bridge the VM to a tap0 interface instead.

[Aleksey Ilyushin]

Jeremy, can you try the patched file I attached to #3056? The instructions are in the comments there. This may solve the problem with IPv6 configuration.

[Jeremy Visser]

Yes! That patch fixes it! I tested with several reboots, reconfigurations, etc. before the patch, and as soon as I applied the patch, IPv6 magically started working.

Though this ticket was reported earlier, this ticket should be marked as a duplicate of #3056, as it gets to the bottom of the problem.

Thanks very much, Aleksey.

[Aleksey Ilyushin]

Duplicate of #3056 (which states the root cause of the problem).