DNS reverse lookup zones

[michealallen]

Hi all,

I have an issue with my DNS. There are so many duplicated IPs in the reverse lookup zones in the subnet. For example,
11.199.1.3 Pointer (PTR) machine1
11.199.1.3 Pointer (PTR) machine2
11.199.1.3 Pointer (PTR) machine13
11.199.1.3 Pointer (PTR) machine14
....
Some of the computer names are old. Question is, why are they duplicate? Something wrong with DNS server? How can I find out which DNS server is the primery one? I did ping 11.199.1.3 -a does not give me the name of computer.

Thanks,
MA

 

[juniper911]

Michael

When the records were orginally created, you could also create the reverse pointer record at the same time. Over time, you have had different machines use the same IP so that is why you have the multiple pointer records with the same IP but different computer name.

Try to log on workstation via RDP by using IP only and then confirm what the hostname is. Once you've done that delete all the obsolete pointer records. In future when you want to delete DNS records, you do get an option to delete the associated pointer record too.

 

[ITPangaeaArchitect]

sounds like dhcp may not be configured to clean up forward and reverse dns records when the lease expires

ensure dhcp is set to always update dns and to clean up dns records when the lease expires.

-Brandon Wilson
MCSE:Security00/03
MCSA:Messaging00
MCSA:Security03
A+