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DNS reverse zone active directory

hi, i have a question about reverse zones for my active directory environment.

Lets say site A, is a super netted site.
within that supernet, are smaller networks

subnet A
subnet B
Subnet C
Subnet D
Subnet E
Subnet F
Subnet G

For reverse zones, is there a way to define the entire subnet either by the /19, or example subnet A with the /23 or do i have to define each one the way it is presented in the wizard, as in since 32 total subnets in that /19
i would have to define each /24 subnet?
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1 Solution
Chris DentPowerShell DeveloperCommented:
Only by creating the zone as /16, but there are no other choices, reverse lookup zones follow classful addressing boundaries (/0,  /8, /16, /24 and /32 only).

This isn't an MS limitation (or a limitation of the wizard), it's a limitation in the DNS service.

Svet PaperovIT ManagerCommented:
Yes, classless reverse lookup zone can be created but there is actually one situation when it will make sense – when you are delegated with managing a subnet of a classful network. Otherwise, just stick with the classful ARPA standard. The following example is for Windows Server 2000 but it will work in 2008 too. http://technet.microsoft.com/en-us/library/cc961414.aspx
Chris DentPowerShell DeveloperCommented:
Classless zones are entirely reliant on delegation from a classful zone. It needs a CNAME to rewrite from one zone to another. You'd still need to create the /16, and your overhead would be significantly greater.

Be aware that classless reverse lookup zones cannot be dynamically updated. This is mentioned in the article linked above, but it's easy to miss:

No Dynamic Updates on a Classless Reverse Lookup Zone

I strongly suspect this also applies to Server 2012 and 2012 R2.
Chris DentPowerShell DeveloperCommented:
(for confirmation) It will, the nature of classless zones prohibits (RFC compliant) dynamic update methods.


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