IPv6 6RD testing

[dane]

Once we have deployed native IPv6 with 6RD in our CPE platform, we will retire the older tunnel system. It doesn't have the same level of performance, capacity and redundancy that the new production platform has.

[nwhitehorn]

Thanks very much for the direct clarification! I've switched over to 6RD, which is working great.

[dane]

Thanks very much for the direct clarification! I've switched over to 6RD, which is working great.

Kelsey has corrected me, says we have no plans to decommission old system. FYI!

[davidstrauss]

While someone's posted earlier in the thread with an example Cisco ISR configuration, I'd also like to offer ours. It's different because we're using separate WAN and LAN NICs and use a later model (Cisco 2911 ISR). We also use stateless DHCPv6 to provide IPv6 DNS IPs, which anyone wanting to also support pure IPv6 clients needs to do.

999.999.999.999 is the intentionally invalid placeholder for our office's main public IPv4 address. We use the 255.255.255.240 mask because we're business ethernet customers with a small, contiguous IPv4 block.

Here are the relevant IPv6 excerpts:

Code: Select all

ipv6 general-prefix DELEGATED_PREFIX 6rd Tunnel0
ipv6 unicast-routing
ipv6 dhcp pool LAN6
 dns-server 2001:4860:4860::8888
 dns-server 2001:4860:4860::8844
 domain-name office.example.com
ipv6 cef

interface Tunnel0
 description Sonic.net IPv6 Tunnel
 no ip address
 no ip redirects
 ipv6 address DELEGATED_PREFIX ::/128 anycast
 ipv6 unnumbered GigabitEthernet0/0
 ipv6 enable
 tunnel source GigabitEthernet0/1
 tunnel mode ipv6ip 6rd
 tunnel 6rd prefix 2602:240::/28
 tunnel 6rd br 184.23.144.1

interface GigabitEthernet0/0
 description LAN
 ip address 10.0.0.1 255.255.0.0
 ip nat inside
 ip virtual-reassembly in
 duplex auto
 speed auto
 ntp broadcast
 ipv6 address DELEGATED_PREFIX ::/64 eui-64
 ipv6 enable
 ipv6 nd other-config-flag
 ipv6 dhcp server LAN6 rapid-commit

interface GigabitEthernet0/1
 description SonicWAN
 ip address 999.999.999.999 255.255.255.240
 ip nat outside
 ip virtual-reassembly in
 duplex auto
 speed auto

Cisco has a useful page on its wiki that I used:
http://docwiki.cisco.com/wiki/6rd_Configuration_Example

[windwave]

Unable to reach ipv4 address of 184.23.144.1 . Seems to stop in 208.106.96.249 unreachable 69.12.211.118 sent me to the 208.106.96.249.

Is there a problem in the ipv4 routers.

Ben Bigelow

[Guest]

It seems to ping fine for me, but it's probably specific to your region.

[Guest]

you ping is from santa rosa, ca. i am comming thru san francisco offices .. i think diferent routers.

[nwhitehorn]

One issue I've noticed is that the 6RD reverse DNS seems to have issues. In particular, looking up addresses returns SERVFAIL instead of NXDOMAIN. I guess the authoritative name server is either not set or not responding. This causes noticeable delays when logging in to services (ssh, for example) that try to get a host name. Actual reverse DNS would of course be nice, but setting up a server that just immediately returns NXDOMAIN would be a huge improvement for your 6RD service.

[gkeller]

The rDNS for the 6RD addresses should be working now. Let us know if you have any problems.

[nwhitehorn]

Working great. Thanks for fixing it!