Ping IPv4 to IPv6

[tristan.munier]

Hi, i asking you for an advice, i'm actually in trainsheep and i've to configure a routeur Cisco ASA 5506-X and I want to ping an IPv6 machine with an IPv4 machine. i saw they are differents solutions, but i don't find any forums or website to explain how to configure a routeur in NAT-64.

Thanks for the help and i'm sorry if the question have been already ask by another people, i'm new on the forum and i don't know everything.

Tristan.

[Philip D'Ath]

Make life simple, and go dual stack.

[James Leinweber]

IPv4 and IPv6 don't inter-operate in general, and ICMP (IPv4 protocol 1) and ICMPv6 (IPv6 next header 58) don't inter-operate in particular.  Most NAT64/DNS64 translators I've heard of concentrate on UDP and TCP; I'm not sure what ICMP translations they might also do.  However, they are designed for the IPv6 -> IPv4 direction only; NAT-PT to go up from IPv4 to IPv6 was deprecated and you aren't likely to find good implementations anywhere.

NAT64/DNS64 is an answer to the question of "my ISP is only offering native IPv6 last-mile, how do they get me to a IPv4-only TCP service?".   I'm with Philip; do not try to use IPv6 from an IPv4-only device.

-- Jim Leinweber, WI State Lab of Hygiene

[tristan.munier]

My problem is that, i have a device who have an IPv4 adress and an IPv6 adress on the same ethernet card, i want him to send files, ping or anything who have to get in and go out of the router, but à the exit of the router, i just want an IPv4 translation.

[James Leinweber]

If you are dual-stack on your LAN, you can talk to local, directly-attached hosts using either IPv4 or IPv6.  The default would be IPv6, if both resolve in DNS.  Probably your inside IPv4 is on RFC-1918 private addresses, which aren't routable off-site and require NAT44 translation at your router.  If your router doesn't have IPv6 upstream, your local IPv6 is probably link-local scope addresses starting with fe80::/64, which aren't routable off-link. These are comparable to IPv4 autoconf addresses 169.254.0.0/16, which also aren't routable. Global scope IPv6 addresses which can be routed planet-wide all start with 2000::/3.  The typical situation for networks which have live dual-stack uplink is that the LAN hosts configure with private IPv4 and both link-local and global IPv6, with the IPv4 getting NAT44 translation to uplink, the link-local IPv6 staying local, and the global IPv6 passing unchanged.

If the issue is not leaking IPv6 onto the internet, not having an IPv6 uplink at the router will do that.  If the issue is trying to translate IPv4 into IPv6, forget it; you want native or nothing.  The automatic encapsulated IPv6 over IPv4 transport tunneling protocols that windows 7 would try (ISATAP, 6to4, Teredo) are pretty much all dead, as there are no upstream gateways for them to talk to anymore.

-- Jim Leinweber