Hmmm. You're probably not missing anything — there haven't been any GUI settings added for managing IPv6 subnets, and I don't think anything has been tested or written to ensure IPv6 is working in bridging configurations.
Is the wireless mode on the GL set to "Wireless Ethernet Bridge" or "Wireless Client" ?
If "Wireless Ethernet Bridge": it *probably* should automatically work, but I wouldn't be surprised to hear it doesn't. I'm not really familiar with how that's set up but I think that mode is mostly a function of the (closed source) Broadcom wireless driver, which would make hard to fix to work as it should. You could, as a workaround, do what I describe for the other case, but then your IPv4 and IPv6 subnets won't line up, which could cause problems/weirdness.
If "Wireless Client": it won't work on its own, you'll need to configure the second router to advertise its own IPv6 subnet, and set the first router to route that subnet.
You're with TekSavvy, right?
Let's assume the /56 prefix they assigned you was 2607:f2c0:1234:ab00:: — those last two zeros there are the 8 bits you can use to define your own subnets (individual subnets are normally /64 bits in IPv6). The following directions should set the first router to use […]:ab00::/64, the second router to use […]:ab01::/64, and tells the first router to send traffic for that second subnet to the second router.
- Make sure the IPv6 prefix on the first router is set to 2607:f2c0:1234:ab00:: and prefix length 64. Enable Router Advertisements. That's the important part. You can leave the Router IP field blank and it will default to 2607:f2c0:1234:ab00::1
- On the second, client router, set the IPv6 mode to Native, and the prefix to 2607:f2c0:1234:ab01:: with prefix length 64, and enable Router Advertisements.
- Figure out what the second router's link-local address on its Wifi interface will be. With the GL, if IPv6 is already enabled on it, you can check this by running
ip -o -6 addr show dev eth1 scope link
Alternately, you can figure out what this will be by looking at the MAC address (listed in the wireless section of Basic Settings); it's pretty simple:
If the MAC address is 00:14:BC:4A:B3:67 then it's link-local IPv6 address will be fe80::0214:bcff:fe4a:b367, which is (roughly) derived as follows:
- Always starts with fe80::
- the first digit of the mac address, THE SECOND DIGIT PLUS TWO, the third and fourth digits, then colon.
- 5th and 6th digits, then "ff:fe"
- then the rest of the MAC address, with a colon placed appropriately so that everything is nicely divided into four-character segments.
Once you have that address, add a line to the Init script of the *first* router to establish a route pointing to the second, e.g.:
ip route add 2607:f2c0:1234:ab01::/64 via fe80::214:bcff:fe4a:b367 dev br0
This is all off the top of my head. It *should* work but I'm not in a position to test it at the moment, so there might be minor glitches.
Later this week I'll have a chance to borrow a router my brother isn't using so I can actually test this, and probably make some simple changes that should make the last step unnecessary.
SonicSam (guest) 13 Feb 2011 23:46
