I am trying to implement some DHCP Reservations. It is on a SBS 2011 Server. When I look in the DHCP under Address Leases I see BAD_ADDRESS with a description "This Address is ALready In Use".

   I am assuming it means the IP address is already in use? When I sort the leases there is only one that shows up. How can I tell what other device is using (if that is the problem)
LVL 15
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Cliff GaliherCommented:
That's the problem. And it usually means another DHCP server handed out that address (but SBS usually shuts down its DHCP server if another is detected) or that address was statically assigned to a device.

You can use arp -a to get a list of known IP addresses and their associated MAC addresses. But then you still get to hunt down the device.  And that is entirely environment dependent.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
LockDown32OwnerAuthor Commented:
Well.... it look like it already assigned 132 which is normal. I am adding the reservations after the fact and will be stepping on some already assigned IP address. So how to you implement reservations "after the fact"?
JohnBusiness Consultant (Owner)Commented:
We had exactly that problem on Server 2012. Same message.

We found a machine that was supposed to be Reserved A but was in fact on Reserved B in error and so that address was in use. It was necessary to find out which of the reserved devices was wrong and fix it.
OWASP: Threats Fundamentals

Learn the top ten threats that are present in modern web-application development and how to protect your business from them.

Radhakrishnan RSenior Technical LeadCommented:

Perform nslookup against the IP address and see it resolves to which host? and make sure that you reserving with appropriate mac id.
LockDown32OwnerAuthor Commented:
There is only one DHCP server. It is the SBS 2011 Server. What is was doing made sense. When the day started out 132 was assigned by the DHCP server. Then I decided I wanted to reserve that IP and since it was already assigned I got the error.

   So what I did was re-define my scope so it wouldn't pass out IPs in the range I want to reserve and rebooted. Still getting the BAD_ADDRESS error but not if the IP should be in use at this point. So now what?
JohnBusiness Consultant (Owner)Commented:
There is only one DHCP server. .....Still getting the BAD_ADDRESS error but not if the IP should be in use at this point. So now what?

You need to find the offending devices - process of elimination
LockDown32OwnerAuthor Commented:
That was a pain. Even re-assigning the range on the scope and rebooting the workstations did not release their IP address. I had to go to each computer individually and release it. Did finally get all the reservations added and it appears to be working.
JohnBusiness Consultant (Owner)Commented:
Thanks. Yes! It was a pain for us as well, and partly good luck that we found the machine relatively quickly
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.