# [Solved] IPv6 routing poblems

## Bullet Dodger

I have a home built IPv6 router which can ping IPv6 addresses, but a host connecting to the router can not.

I have a router with the following set up:

```

    |192.0.43.10 (public ipv4)

+-------- Router ---------------------+

|   |                                 |

|  eth0                               |

|  192.0.43.10                        |

|   |                                 |

| +-----------------------------+     |

| | br0                         |     |

| | 192.168.0.1                 |     |

| | (eth1, wlan0)               |     |

| +-----------------------------+     |

|     |      |                        |

|     |      +---------+              |

|     |                |              |

+-------------------------------------+

      |192.168.0.1     |192.168.0.1

```

My public IP address has been replace by the IP address for example.com (because, admit it, if I'd given you my real address you'd be tempted to have a look).

As my ISP doesn't yet support IPv6, I set up a 6to4 tunnel.

I now have the following:

```

                                       192.88.99.1  +--- 6to4 relay --+

   Internet(IPv4) ----------------------------------|-----------------|--- Internet IPV6

    |                             2002:c058:6301::  +-----------------+

    |192.0.43.10 (public ipv4)

+-------- Router ---------------------+

|   |                                 |

|  eth0 -------- 6to4 (sit0)          |

|  192.0.43.10   2002:C000:2B0A::1/48 |

|   |            (public ipv6)        |

| +-----------------------------+     |

| | br0                         |     |

| | 192.168.0.1                 |     |

| | fe80::20e:c6ff:fe88:9ae9/64 |     |

| | (eth1, wlan0)               |     |

| +-----------------------------+     |

|     |      |                        |

|     |      +---------+              |

|     |                |              |

+-------------------------------------+

      |192.168.0.1     |192.168.0.1

      |                |

                       |

                    +-------- Computer 1 ---------------------+

                    | 192.168.0.19                            |

                    | 2002:C000:2B0A:f101:6233:4bff:fe2c:3650 |

                    |                ----                     |

                    | Router: fe80::20e:c6ff:fe88:9ae9        |

                    +-----------------------------------------+

```

The public IPv4 address is 192.0.43.10 (example.com)

Public IPv6 address 2002:C000:2B0A::1/48 (6to4 conversion of 192.0.43.10 to IPv6).

The bridge (br0) shouldn't been needed for IPv6 connectivity, but as it works on the ethernet layer, should have no effect on the IPv6 layer.

The bridge has an link local fe80:... address. I don't know if this is correct or not.

Computer 1 has the network prefix of the router (which is in this case is replaced by example.com - 2002:C000:2B0A. I don't know where the subnet f101 has come from though).

The router is using the anycast 6to4 ip address 192.88.99.1 (IPv4) 2002:c058:6301:: (IPv6)

The router can ping6 ipv6.google.com

The router can ping 192.88.99.1

The router can ping6 2002:c058:6301::

Computer 1 can ping6 the routers bridge link-local ipv6 address

```

$ ping6 -n ff02::1%en0

PING6(56=40+8+8 bytes) fe80::6233:4bff:fe2c:3650%en0 --> ff02::1%en0

16 bytes from fe80::6233:4bff:fe2c:3650%en0, icmp_seq=0 hlim=64 time=0.265 ms

16 bytes from fe80::20e:c6ff:fe88:9ae9%en0, icmp_seq=0 hlim=64 time=3.355 ms

```

(For anyone that noticed, computer 1 is a mac, which is why the interface is %en0)

Computer1 can not ping6 ipv6.google.com or 2002:c058:6301:: (6to4 relay)

What am I missing?Last edited by Bullet Dodger on Tue Jan 24, 2012 3:44 pm; edited 1 time in total

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## Bullet Dodger

Something I forgot to mention, is I tried to add the route:

```

# ip -6 route add 2000::/3 via 2002:c058:6301::

```

Computer1 still can not ping6 any IPv6 address

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## gerdesj

Have you enabled forwarding? See http://www.gentoo.org/doc/en/ipv6.xml section 5.

Cheers

Jon

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## Bullet Dodger

I solved this by making sure the 6to4 interface had an ip 2002:C000:2B0A::/48 and the bridge had 2002:C000:2B0A:1::1/64, then I didn't need to create any additional routes. Still not entirely sure why this worked. I did find that setting the bridge to 2002:C000:2B0A::1/64 would not work

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