Distributing IPv6 to multiple VLANS
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I have IPv6 working between the WAN and LAN segments but don't know how to add it to a VLAN i/f.
The LAN config is set to tract WAN interface. When I try to do the same for the VLAN i/f I get that the tracking interface is in use by the LAN segment.
The WAN config is DHCP6. ISP Spectrum (yeah, I know).
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Assuming your ISP provides multiple /64s, you choose a different Prefix ID for each VLAN. How many /64s do you get? I have a /56 prefix, which provides 256 /64s. Others get a /48 for 65536 /64s or /60 for 16. For example, with a /56, my prefix IDs range from 0 - ff. I use 0 for the main LAN, 4 for a test LAN and ff for my VPN.
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Make sure you set the correct DHCPv6 Prefix Delegation size for your ISP (e.g. 56) in the DHCP6 Client Configuration of the WAN interface. You probably also have to set "Send an IPv6 prefix hint to indicate the desired prefix size for delegation". If this works, then go to the LAN configuration and set the IPv6 Prefix ID in the Track IPv6 Interface configuration.
What I usually do:
- My prefix size is 56 bit which means I have 256 (= 64bit - 56bit = 8 bit) IPv6 Prefix IDs available.
- In my IPv4 setup, I have /24 networks, i.e. 192.168.x.0/24, so I have 256 networks available as well.
- To keep it well organized, I set the VLAN ID, the IPv4 network (so x above) and the IPv6 Prefix ID (converted to hex) to the same number. E.g. VLAN 25, IPv4 192.168.25.0/24, IPv6 Prefix ID 19.
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@HG said in Distributing IPv6 to multiple VLANS:
To keep it well organized, I set the VLAN ID, the IPv4 network (so x above) and the IPv6 Prefix ID (converted to hex) to the same number. E.g. VLAN 25, IPv4 192.168.25.0/24, IPv6 Prefix ID 19.
Me too, except I have IPv4 in the 172.16.x.0/24 range. I went with that to avoid conflicts when travelling, when I used my VPN.
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I've been trying all the permutations just on one internal segment and it looks like the local Spectrum is only providing a /64. I've tried /56 and /60 and am working through the permutations of send hint or not. The problem is they are sporadic in sending IPv6 configs so I have to reboot the modem each time and wait,
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Maybe you can call their support line and ask. Or perhaps they have a support forum, the way my ISP does.
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@JKnott I would rather chew glass than deal with Spectrum (aka Speculum) "tech support".
At least they're offering native IPv6, FiOS STILL isn't offering it.
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FINALLY, success!
After retrying what should have worked the first time, but didn't, I can report I have a /56 and proper delegations to the different segments.
The problem was the ISP, even after a modem reboot, would be inconsistent issuing IPv6 configs. It was 24 hours of tweaking and rebooting.
Thanks for the advice, it did help to narrow down the options.
