The ip6.int domain has been deprecated for some time now, see RFC 3152 - Delegation of IP6.ARPA and RFC 3596 - DNS Extensions to Support IP Version 6. As of the 1st June 2006 ip6.int will be truly obsolete as the DNS domains that provide the answers will no longer be maintained.

As the title of the above RFCs allude the ip6.int domain has been replaced with the ip6.arpa domain.

IPv6 reverse addressing was originally founded within the .int domain following RFC 1591 which declares the .int domain is used for "organizations established by international treaties, or international databases." In 2000 the Internet Architecture Board (IAB) recommended that any new infrastructure sub-domains be established within .arpa (Address and Routing Protocol Area) and that consideration be given to migrating existing infrastructure sub-domains in .int to .arpa. Subsequently as of the 1st of June 2006 maintenance of the ip6.int domain will cease.

Why is an ip6 domain needed?

It is fair to say that we humans mostly deal with names, such as sun.com. And underneath the hood of the application this name is converted using the function gethostbyname() to a sequence of numbers known as the Internet Protocol address, or IP address which the computer then uses to connect to other computers. To lookup the name within DNS the domain name it self is used as reference list, DNS asks the root servers 'who is the .com server?' DNS will then ask a .com server 'who is sun.com?' Eventually obtaining the IP address through delegation.

So when computers talk to each other they use the IP addresses which often then needs to be translated into host names for our consumption. This is commonly known as an inverse address resolution and is accomplished using the function gethostbyaddr(). The problem is then how to lookup an IP address when the owner of the address is in some currently unknown domain name. This is where the inverse address domain is used. As with the host name, the address is converted into a name by reversing the order of the address and appending the inverse address domain name providing the first starting block in discovering whom the address belongs to.

What does this change in domain name mean for the Solaris Operating Environment?

If your not using IPv6 addressing then this change really does not effect you at all.

If your using IPv6 addressing on Solaris 10 OE or later then you need not take any action as the DNS components provided in Solaris 10 currently use the ip6.arpa domain.

Older supported releases of the Solaris OE may require patching. For information on how to check if your system uses IPv6 addressing and for relevant patch informtion refer to SunAlert 102442

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