IPv4 over IPv6



  • My ISP assigns a single /64 IPv6 address through DHCPv6. It cannot be delegated. To get a somehow decent connectivity, the modem I was given creates an IPv4 over IPv6 tunnel.
    Using IPv4 directly I have 70ms latency to the first hop and about 20% packet loss at any rate.

    While I can make it work on Linux, I was unable to find any way to set up the tunnel in pfSense, not even using the CLI.
    Is there any documentation on how to do it? I sent a substantial amount of time googling it, but I could not find anything.


  • LAYER 8 Netgate

    What did you do in Linux to make it work?



  • Thanks for your reply Derelict. The commands that creates the tunnel is

    ip -6 tun add sit1 mode ipip6 local <client IPv6 address> remote <server IPv6 address> interface <interface>

    Then I set sit1 as default gw. The process is well explained here, http://linux-hacks.blogspot.com/2008/02/howto-ipv6-ipv6-tunnel-and-ip4-ipv6.html



  • I guess this feature is not available on pfSense. It is a sad news as the situation will become worse over time.

    • IPv6 over IPv4 was the 1st phase of IPv6 implementation.
    • Now we are on the second phase were we are moving to IPV4 over IPv6, as ISP started increasing their IPv6 capable gear. We will see this increasing and this phase will last years
    • IPv4 will eventually go away. However, looking at the trend, I wont be surprised if it takes over 30 years to get there.

Log in to reply