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cvmiller / v6brouter

IPv6 bridge and IPv4 router (NAT) shell script for OpenWRT
GNU General Public License v2.0
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Is it possible to bridge PPPoE IPv6 #1

Closed brshw closed 8 years ago

brshw commented 8 years ago

I get both IPv4 and IPv6 addresses from my ISP using PPPoE, and I use OpenWrt. Is it possible to set it up as a v6brouter?

IPv6 is set up automatically with the default network configuration with pppoe protocol:

network.wan.proto='pppoe'
cvmiller commented 8 years ago

Sorry, but I doubt it. I believe ebtables (the linux bridge that is used by v6brouter) will only bridge ethernet to ethernet, not ppp to ethernet.

But do you need it? If your upstream provider is providing an IPv6 address over PPPoE, are they not also providing Prefix Delegation (via DHCPv6-PD)? Have you looked at the OpenWRT IPv6 networking page? https://wiki.openwrt.org/doc/uci/network6

brshw commented 8 years ago

I do have globally routable IPv6 for my LAN. The reason I prefer this brouter set up is that it bypasses routing on weak hardware. Is there another way to avoid IPv6 routing for PPPoE?

cvmiller commented 8 years ago

It sounds like you are concerned about the performance of your router. Technically bridging should be faster than routing (since the packet remains unchanged when forwarding ethernet packets), but since both are happening in the kernel (with v6brouter/ebtables), I suspect you won't see much of a performance difference.

I just did some reading up on ebtables, and it may supporting bridging between ppp and ethernet (which isn't just bridging since I had to make up a MAC address for the ethernet side, and remember it when it sees a packet come back in on the ethernet interface, and remove it, and put on a PPP header, recalc FCS, and such. So again, if you are concerned about performance, I suspect this isn't the solution for you.

That said, if you edit v6brouter script to point to your ppp-wan interface OUTSIDE=ppp-wan

And run the script and see what happens. The easiest way you will know it is working is that your nodes on your LAN will have the same prefix as your current WAN interface.

HTH

brshw commented 8 years ago

brctl addif returned "Invalid argument" when I tried to bridge PPPoE. Bridging PPPoE probably isn't straightforward as it doesn't really operate in layer 2.

cvmiller commented 8 years ago

As I originally suspected, the kernel doesn't support bridging across different L2 types.