IPv6 6over4 tunnels with Windows and Cisco

mpoulson — Tue, 18 Jan 2005 18:27:00 GMT

A few years ago I began working with Art Shelest here at Microsoft to get Native IPv6 running in my lab. After a few weeks we had it up and running.

We had to work with MSIT (was known as ITG at the time) to get a 6over4 tunnel setup so that we could connect to the 6bone even though my upstream routers did not support IPv6 (still don't at this time). Once the tunnel was setup on the ITG Router we ran a command on my Windows IPv6 Router in my lab and it was up and running.

We run our entire lab IPv6 network on Windows Routers. We use Windows Server 2003 but you could use Windows XP Pro if you wanted. Unlike RRAS the IPv6 routing stack is included in Windows XP. And after Windows XP SP1 this stack was fully supported by Microsoft support. So if you follow the steps at http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/sag_ip_v6_imp_lab_node.mspx you can get your internal test network setup.

Now to create a 6over4 tunnel to another router you simply run the below commands from a cmd prompt on your main IPv6 router

netsh
int ipv6
add v6v4tunnel interface="V6v4 Tunnel" localaddress=<local ipv4 address> remoteaddress=<remote ipv4 address>
set interface "v6v4 Tunnel for=en
add address int="v6v4 tunnel" address=<IPv6 address from provider>
add route ::/0 "v6v4 tunnel" <remote IPv6 address> publish=yes

Key things to note with the above

The Local IPv4 address is the IP address that the tunnel is going to use to talk to the Upstream V6 Router (With my example below it would be 1.1.1.1).
The Remote IPv4 Address is the IP address of the upstream V6 router (with my example below it would be 2.2.2.1).
The IPv6 address from provider would be a IPv6 address that you get from your v6 provider (with my example below it would be 3ffe:ffee:100:2::2)
The Remote IPv6 address is the IPv6 address of the upstream IPv6 router (with my example below it would be 3FFE:FFEE:100:2::1)

The Cisco side of the config looks like this

interface Tunnel1
description v6in4 tunnel to lab 1.1.1.1/3FFE:FFEE:100:2::2
no ip address
ipv6 address 3FFE:FFEE:100:2::1/64
tunnel source 2.2.2.1
tunnel destination 1.1.1.1
tunnel mode ipv6ip

Once the machines are all setup important things to know are "how do you back up your ipv6 configuration?" Well with netsh it could not be easier.

Simply run 'netsh int ipv6 dump > c:\ipv6backup.txt' this will dump all the ipv6 config out to the txt file. Now if the router was to ever go down you can run the command 'netsh exec c:\ipv6backup.txt'. With these 2 commands it will backup and restore your ipv6 configuration.. You can also modify the backup command to be 'netsh dump > c:\netshbackup.txt' and it will back up 99% of all the settings for your network configuration.

If you would like to know more about how I have my IPv6 network setup please let me know. Also I recommend the Microsoft Press Book Understanding IPv6 (http://www.microsoft.com/MSPress/books/4883.asp) ISBN: 0-7356-1245-5

Regular Expressions and IP addresses (ipv4 and IPv6)

mpoulson — Mon, 10 Jan 2005 17:37:00 GMT

Over the last year or so I have been writing automation that uses IPv4 and IPv6 addresses. In the beginning I had to dig up and make some regular expressions for verifying that a given value was a valid IPv4 or IPv6 address.

The ones I came up with are (in VB.net)

Const strIPv4Pattern as string = "\A(25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}\z" 'IPv4 Address Regex pattern (x.x.x.x)

Const strIPv6Pattern as string = "\A(?:[0-9a-fA-F]{1,4}:){7}[0-9a-fA-F]{1,4}\z"

Const strIPv6Pattern_HEXCompressed as string = "\A((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)::((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)\z"

Const StrIPv6Pattern_6Hex4Dec as string = "\A((?:[0-9A-Fa-f]{1,4}:){6,6})(25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}\z"

Const StrIPv6Pattern_Hex4DecCompressed as string = "\A((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?) ::((?:[0-9A-Fa-f]{1,4}:)*)(25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}\z"

Now because an IPv6 address can take a few forms we have 4 different expressions for IPv6. If someone finds a bug in one of these please let me know. Because RegExp is something that I am not good at.

Hope these will help some one.

Mike Poulson's Thoughts on lots of stuff : IPv6

IPv6 6over4 tunnels with Windows and Cisco

Regular Expressions and IP addresses (ipv4 and IPv6)