DNS and IPv6 in Windows Server 2008

[Tuhina]

I am having better knowledge about the concepts of search fields, records and reverse lookup zones. I am looking for some explanation about how IPv6 DNS is supported on Windows Server 2008 (R1 or R2), system on which the support for IPv6 has started to be really effective. Also it would be much grateful if you explain in details about the IPv6. I am sure that you members will help me soon (as usual).

[Nurhan]

Namely that IPV6 is supported at Microsoft (in terms of network connectivity) from Windows XP (you need to install SP3 it and add a protocol in the properties of the map, it is enabled natively on newer systems). The two main interests of the establishment of support for IPv6 saves time for customers in IPv6 (which no longer have to juggle between the protocols and gateways to connect to a host) and preparing your infrastructure for the arrival of this new protocol on the Internet. IPv6 is the culmination of the work within the IETF in the 1990s as a successor to IPv4. With addresses of 128 bits instead of 32 bits, IPv6 has an address space much larger IPv4. This considerable amount of addresses allows greater flexibility in assigning addresses and aggregation of roads in the Internet routing table. The address translation, which was made popular by the lack of IPv4 addresses, is no longer necessary.

[Abraham.J]

IPv6 also provides mechanisms for automatic address assignment and renumbering easier. The size of the subnet, IPv4 variable was set to 64 bits in IPv6. Security mechanisms like IPsec are part of the basic specifications of the protocol. The header of the IPv6 packet has been simplified and the types of local addresses facilitate the interconnection of private networks. The deployment of IPv6 on the Internet is complicated because of the incompatibility of IPv4 and IPv6. Address translators automatic face significant practical problems (RFC 4966). During a transition period where IPv4 and IPv6 coexist, hosts have dual stack, that is to say they have both IPv4 and IPv6 addresses, and tunnels allow passing groups routers that do not yet support IPv6. As a reminder, IPv6 is the communication protocol (network protocol) need to replace IPv4. Internet is based on these protocols to operate. It is phased in over the network since 1996 (published in IPv6 RFC 1883, December 1995) to compensate for certain problems in IPv4:

• Exhaustion of IPv4 addresses that gave rise to "tricks" such as NAT, PAT ...
• Overconsumption processors routers that were recalculate the hash of each packet header as the number of hops remaining was included in the header.
• Headers of variable size which increased the difficulties of implementation.

[Barsha]

In terms of unicast addresses, the Internet is divided this way:

• prefixes / 23 are attributed to regional Internet registries.
• these networks are redistributed into networks / 32 that are allocated to your ISP.
• ISP cut back its network to assign a prefix / 48.
• you can redraw your network into / 64 to differentiate your geographical sites or networks (in particular deals, the ISP assigns a network often directly / 64).

You should also keep in mind that not to exceed 64 bits prefix length or you will ruin the AutoConf, faculty as a client to match the local address with its public address. Note that with IPv6, every host on the network has one or more public IP addresses.

[B_Hodge]

An obvious prerequisite is to not have disabled IPv6 on the network interfaces the DNS server. As a reminder, Active Directory is the directory service from Microsoft and it relies on DNS to function properly. It maintains a DNS zone automatically. Please understand that this role is not required though often present in the actual infrastructure. Similarly, the IPv6 connectivity to the Internet is not fundamentally required for the DNS with IPv6. Nevertheless, it is preferable to have it. When a machine has both connectivity in IPv6 and IPv4, and it must resolve an FQDN, it will make the first query the corresponding AAAA record type and then query the type A record (just try it first to contact the designated host FQDN to IPv6 and IPv4). A best practice in the management of DNS that either IPv4 or IPv6 is to specify host names for the record type service (SRV, MX, MB ...) and not an IP address directly. This will force the client to make two requests to locate the service but will allow easier maintenance and facilitate the implementation of IPv6.

[Rock Villa]

The more observant among you will notice that the last four groups of letters are identical on both IPv6 addresses, IPv6 is a feature if your router and DHCP server are properly implemented, it matches local address (starting with fe80 or FEC) for public administration and easier. In the Forwarders tab, you can find the servers to query when your DNS infrastructure is not the answer, it will add IPv6 addresses of DNS servers of your ISP. Similarly, in the tab "Specifying root" you must add each IPv6 root server by clicking edit on each server; you can easily find these addresses on the Internet. So you come to see the properties of your DNS server set up, as you may have noticed there is no real change, and you must not forget however that these operations will be performed on all servers your infrastructure.

[Pollock]

The main novelty found in the management of the DNS with IPv6, and more specifically in areas of direct search are the new AAAA records. Indeed, they are equivalent to the A record in IPv4. Best Practice, to maintain maximum compatibility before the final abandonment of IPv4 it is advisable for each host name (or FQDN) to inform the record type A and the corresponding AAAA record. To reduce administrative effort and then only if your router / DHCP server is configured correctly I suggest you also specify only the public IPv6 address (not to create two records for a single AAAA DNS), your router will match the with the local link. While there is no correspondence between the public and local IP address that is not embarrassing (the traffic will pass through the router just so that might have remained on the LAN). Obviously if you have IPv6 firewall in place between the LAN and Internet (highly recommended) and it does not match this may not work (since your machines "will come from outside" in the eyes of firewall, the port will be blocked). Best Practice, it is best to configure the first or reverse lookup zones, so you can check the automatic creation of PTR (corresponding records but for the reverse lookup zone).