Hi,
To configure your DNS for reverselookup you need to add a in-addr.arpa zone. If you have a class C network with the IP's 192.168.7.x you must name your zone: 7.168.192.in-addr.arpa for a class A Network with IP's 10.x.x.x the name ist 10.in-addr.arpa After that you have to create the PTR-Records for your Hosts in this zone.
If you have already many Hosts without a PTR-record and want to add them i suggest you to use a good text-editor like PrimalScript. in PrimalScript you can only select columns of your zone-file containing the A-records and add/append them to your zone-file containing the PTR-records.
it's a little bit difficult for me to explain it in english, so i will try it with an example:
Assuming your File with the A-records looks like that:
HostA IN A 192.168.7.12
HostB IN A 192.168.7.13
HostC IN A 192.168.7.14
HostD IN A 192.168.7.15
HostE IN A 192.168.7.16
Here you can only mark and copy the last octet of the IP-Adress and insert it into your PTR-File, after that you append "IN PTR" to every line. Then you only mark and copy all Hosts and apped them to your PTR-File and add you DNS-Name to every line. After that i should look like this:
12 IM PTR HostA.MYDNS.HOME
13 IM PTR HostB.MYDNS.HOME
14 IM PTR HostC.MYDNS.HOME
15 IM PTR HostD.MYDNS.HOME
16 IM PTR HostE.MYDNS.HOME
Stop and restart the DNS-Service and you are done.