Cisco ASA failover fail if IPv6 enabled

Fri, 02 Oct 2009 11:14:05 +0000

I can’t believe it…

Failover on Cisco ASA silently stops working after you enable ipv6 configuration.

We’re used of stupid Cisco bugs, but this wins it all !

IPv6 over IPv4 tunnel with Mikrotik & Cisco router

Sun, 27 Sep 2009 22:44:15 +0000

Time when native IPv6 network will come right to your home is still far away. So tunneling IPv6 network over IPv4 to some IPv6 enabled site is a way to go.

Configuration is easier than expected and it worked right away. In my case Cisco 7600 series is at the data center where native IPv6 is established and Mikrotik RB450 ( a choice for home router – really powerful and really cheap).

One /64 subnet is assigned for the tunnel (point-to-point) and /48 is then routed to it. Yes. In IPv6 /64 subnet of 18446744073709551616 IPs is used for point-to-point tunnel (2 IPs).

On Cisco 7600 – interface (99.. is a 7600 public IP as 22.. is my home public IP):

interface Tunnel0
description --- test ipv6 in ipv4 tunnel ---
no ip address
ipv6 address 2AAA:BABA:101:1::1/64
tunnel source 99.99.99.99
tunnel destination 22.22.22.22
tunnel mode ipv6ip

and route:
ipv6 route 2AAA:BABA:BEEF::/48 2AAA:BABA:101:1::2

and on Mikrotik:

/interface 6to4 add disabled=no local-address=22.22.22.22 mtu=1280 name=ipv6tunnel remote-address=99.99.99.99
/ipv6 address add address=2AAA:BABA:101:1::2/64 interface=ipv6tunnel
/ipv6 route add disabled=no dst-address=::/0 gateway=ipv6tunnel

And that’s it. You can configure local interface on Mikrotik, like this:
/ipv6 add address=2AAA:BABA:BEEF:DEAD:1/64 advertise=yes interface=ether2

Local machines, if properly configured should receive advertised IPv6 prefix and configure itself for IPv6.

That’s for now, more about IPv6 soon ! HaveAnice !!

IPv6 on Simon Žekar — unix, communications, stupidities

Cisco ASA failover fail if IPv6 enabled

IPv6 over IPv4 tunnel with Mikrotik & Cisco router