DNS Reverse Lookup Zone problem.
Posted on 2011-10-26
We recently expanded a network by stealing a bit from the subnet mask. We went from a 255.255.254.0 to 255.255.252.0. In DNS, there is no Reverse Lookup Zone entry for the two new subnets. My original two subnets both have entries, rather than having a single entry for the network. Should there be only a single entry, and how do I repair/configure this?
I should add that originally, this was a single network of 255 IPs that was expanded by robbing a bit from the subnet mask (from 255.255.255.0 to 255.255.254.0). It has been expanded again by robbing another bit from the subnet mask. Originally, the network was 10.5.17.x and it went to 10.5.16.x and 10.5.17.x after the first expansion. There are two reverse lookup zone entries for this network now, 10.5.16.x and 10.5.17.x. Now that we have 10.5.18.x and 10.5.19.x after the recent subnet expansion, there are no reverse lookup zone entries for them.