I'm trying to run an UML in IPv6 mode on a Linux (Ubuntu) box, and have not been successful with it. I could get the UML to boot up alright, but the interfaces do not seem to accept IPv6 addresses. The file /etc/config/network looks like this:

config interface lan
        option ifname   'eth1'
        option proto    'static'
        option ip6addr  '2001:220:abcd:70::10/64'

Adding it manually doesn’t seem to help either:

root@OpenWrt:/# ifconfig eth1 add 2001:220:abcd:70::10/64
ifconfig: socket(AF_INET6,2,0): Address family not supported by protocol
root@OpenWrt:/# ip -f inet6 addr add dev eth1 2001:220:abcd:70::10/64
RTNETLINK answers: Operation not supported
root@OpenWrt:/# ip -f inet6 addr add dev eth1 2001:220:abcd:70::10
RTNETLINK answers: Operation not supported
root@OpenWrt:/# ip addr add dev eth1 2001:220:abcd:70::10/64
RTNETLINK answers: Operation not supported

I referenced a few OpenWRT links that talk about how to enable IPv6 on the system, and believe I have it in place. Could you please help me understand what is missing or what is the problem?

I'm not sure what relevant information to provide. Please let me know.

This is what is displayed as the startup banner:

BusyBox v1.19.4 (2013-02-10 13:17:40 GMT) built-in shell (ash)
Enter 'help' for a list of built-in commands.
  _______                     ________        __
|       |.-----.-----.-----.|  |  |  |.----.|  |_
|   -   ||  _  |  -__|     ||  |  |  ||   _||   _|
|_______||   __|_____|__|__||________||__|  |____|
          |__| W I R E L E S S   F R E E D O M
-----------------------------------------------------
ATTITUDE ADJUSTMENT (Bleeding Edge, r33315)
-----------------------------------------------------
  * 1/4 oz Vodka      Pour all ingredients into mixing
  * 1/4 oz Gin        tin with ice, strain into glass.
  * 1/4 oz Amaretto
  * 1/4 oz Triple sec
  * 1/4 oz Peach schnapps
  * 1/4 oz Sour mix
  * 1 splash Cranberry juice
-----------------------------------------------------
root@OpenWrt:/#
root@(none):/# opkg install kmod-ipv6
Package kmod-ipv6 (3.2.15-1) installed in root is up to date.
root@OpenWrt:/#

Thanks!