Jade's Tech Notes

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IPv6 via 6rd on Charter With Cisco IOS

Charter does not yet offer native IPv6 but they do have IPv6 via 6rd tunnels for testing. It mostly works but I’ve seen some weirdness with various v6 destinations. Thumbnail images breaking on Facebook periodically and things like that.

Cisco IOS Configuration

I have this working on a Cisco 881W running IOS 15.3(2)T with the advsecurity license.

Enable IPv6:

ipv6 unicast-routing
ipv6 cef

Set up a DHCPv6 pool:

ipv6 dhcp pool home-pool
 dns-server 2607:F428:1::5353:1
 dns-server 2607:F428:2::5353:1
 domain-name home.example.com

Tunnel interface:

interface Tunnel0
no ip address
no ip redirects
ipv6 enable
 tunnel source FastEthernet4
 tunnel mode ipv6ip 6rd
 tunnel 6rd prefix 2602:100::/32
 tunnel 6rd br

Routes & general-prefix:

ipv6 general-prefix DELEGATED_PREFIX 6rd Tunnel0
ipv6 route 2602:100::/32 Tunnel0
ipv6 route ::/0 Tunnel0 2602:100:4472:A501::1

LAN interface:

interface Vlan1 
    ipv6 address DELEGATED_PREFIX ::1/64
    ipv6 nd other-config-flag
    ipv6 dhcp server home-pool