Best practise: Keeping Reverse Lookup Zones "clean"

[Guest]

Dear all,

we've problems with our Reverse Lookup Zone, many IP numbers have
multiple PTR records but each IP should only have one PTR record.
The lease time for DHCP clients is 4 days - and that should not be changed.
Seems that a lot of people experience this problem.

Can anyone tell us what to do best:
1. What to set on the DHCP server
2. What to set on W2K- and XP-Clients (that do DNS-registration themselves)
3. How to set the Aging/Scaveging properties in dependency of the DHCP-lease
time. (Refresh and No-refresh) ?
4. Other ...

Thanks a lot in advance
Juergen

 

[Guest]

Can any of the experts give advise what would be a "Best practise", please.

 

[Guest]

Come on ..... please

Can any of the experts give advise what would be a "Best practise", please.

 

[Kevin D. Goodknecht Sr. [MVP]]

In

Come on ..... please

This is generally caused by clients not releasing the IP address at
shutdown, improper shutdowns, or clients (usually laptops) disconnecting the
network cable without releasing the IP lease.
I have found that adding option 002 will help with clients not releasing the
address at shutdown. As for the laptops there isn't much you can do since
you can't prevent users from disconnecting the cable. Reducing the lease
time can help DHCP keep the zones clean but I would not lease for less than
one day.
This can also be an ownership problem on the reverse zones. This is not a
problem for forward zones because the host name should only be registered by
one owner because the name does not change. For reverse zones it is
different, the PTR name is the IP number so a PTR register under one name
can only be removed by the owner of the record. You can have one IP owned by
several clients in the reverse zone, if the client does not remove its PTR,
the next client that registers the PTR cannot update or remove the previous
owner's PTR record.
Reverse zones are not required for proper AD function, if you want you can
have the reverse zone scavenged daily. But I'd create a static record for
DNS servers so you don't get the old nslookup "can't find servername for
address <ipaddress>" message.

 

[Guest]

Dear Kevin,

thanks a lot for mercy ;-).
What I understood is that you suggest to
- scavenge a Reverse zone every day
- - what exactly should I set for "No-refresh interval" and "Refresh interval"
- - - in the server properties
- - - in the reverse zone properties

What I read in other posts is to create a reverse zone (to prevent internet
name resolution (forwarding) because of a "not hosted" zone), but don't allow
updates.
Is that your opion too ?

What about Option 002 ?
"002 Time Offset Time offset (in seconds) from Universal Time Coordinated
(UTC), aka Greenwich Mean Time "
What should that do in this case ?

Thanks a lot for your help in advance

Juergen

 

[Kevin D. Goodknecht Sr. [MVP]]

In

Dear Kevin,

thanks a lot for mercy ;-).
What I understood is that you suggest to
- scavenge a Reverse zone every day
- - what exactly should I set for "No-refresh interval" and "Refresh
interval"
- - - in the server properties
- - - in the reverse zone properties

What I read in other posts is to create a reverse zone (to prevent
internet name resolution (forwarding) because of a "not hosted"
zone), but don't allow updates.
Is that your opion too ?

What about Option 002 ?
"002 Time Offset Time offset (in seconds) from Universal Time
Coordinated (UTC), aka Greenwich Mean Time "
What should that do in this case ?

Microsoft option 002.
Release DHCP lease on shutdown. 0x1

 

[Guest]

Microsoft option 002.
Release DHCP lease on shutdown. 0x1

That seems to be not a standard use of option 002 ? (I found "002 Time
Offset Time offset .....")

Where can I read more about that ?

 

[Kevin D. Goodknecht Sr. [MVP]]

In

That seems to be not a standard use of option 002 ? (I found "002 Time
Offset Time offset .....")

Where can I read more about that ?

On the Scope or server options properties sheet, Advanced Tab, Vendor Class
field, select Microsoft Options from the drop down list. Then you will see
this option.

 

[Guest]

In

On the Scope or server options properties sheet, Advanced Tab, Vendor Class
field, select Microsoft Options from the drop down list. Then you will see
this option.

Many thanks

Juergen