DHCP Issues

[viper62]

I have an interesting problem. Im running a 2000 network that I took over in July of this year. I run both static and DHCP clients. My DHCP problem is this, in my scope I have 141 addresses and current statistics are:

In Use > 133
Avail > 8

The problem here is that I only have a max of around 30 DHCP clients on my network. Under my address leases in my DHCP server I only show 24 addresses. So where is the other 109 addresses and how can I recover them?

I have checked my DNS server and under the Reverse Lookup Zone I keep seeing addresses show up and yesterday I removed around a 100 that were client related. I have restarted both services and still I am missing over 100 addresses. I have tried changing the lease duration from anywhere between 6 hours and 3 days to no avail. So how can I get these addresses back? Why are they showing up being used when that is not the case. As far as workstation clients go we have 2 shifts and computers are used by more than one person but that should not affect DHCP. Any help would be greatly appreciated as I have been trying to figure this out on and off for the past few weeks.

Thanx,

Michael Farrington

 

[Koonan]

Exclusions? Some people set up large scope but then exclude out a range of addresses. These excluded addresses will show up as "In Use".

Mike


=====================================
The good ole days weren't always good
and tomorrow ain't as bad as it seems
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[viper62]

There is only 1 reservation made. I cant think of anything that would be utilizing over 100 addresses. I presently only have around 65 total employees.

 

[Koonan]

Excluded addresses not reservations, they are different.

Mike


=====================================
The good ole days weren't always good
and tomorrow ain't as bad as it seems
=====================================

 

[viper62]

Yes - Im sorry I meant it as that is all that I have is a single reservation. The only other thing is the scope itself which goes from .60 to .200. It seems pretty straight forward and yet Im missing over 100 addresses. I took this over in July of this year and I am the only Network Administrator. We have a DBA here but he does not know networking at all and would not even touch these services.

 

[viper62]

I have done a temporary solution using exclusions now but I still have about 100 addresses unaccounted for. Is there not any way to track them down and see whats what? Can I not somehow have the dhcp recover all addresses by force . Otherwise the only thing I can think of is to delete the whole scope and recreate it. Any input would be greatly appreciated. Also if you need more info from me feel free to ask. Thanx again...

 

[viper62]

Does anyone have any ideas what is going on with the missing IP addresses? (around 100)

 

[dearingkr]

If you're using the server as a VPN host...

I've seen the server sometimes grab enough ip addresses as there are miniports configured.

MCSE CCNA CCDA

 

[viper62]

Thats good to know but no I do not have a VPN setup at this time. This must be pretty unusual huh?

 

[GlenJohnson]

When is the last time the server has been re-booted. Even if you manually remove some, they may hang out in cache, or show up as duplicates, where only one address shows up more than once. I've been known to re-boot servers on a small network around once a week, just to keep them healthy. I know you should be able to go without re-boots, but I've found them to be more helpful than harmful. Just my opinion though. Good luck.

Glen A. Johnson
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TTinChicago

 

[viper62]

Great minds think alike, I reboot all my servers on every Friday : ) - Doesnt something like this just get your goat. I mean 100 addresses out there and no way to locate them. There has to be a way to force your DHCP server to reclaim all addresses. I had at one point set the lease duration to just 6 hours and still it did not help. I appreciate everyones help - I just hope somehow we can figure this mystery out...

 

[kmcallister]

I would suggest reducing the amount of IPs available for lease, then use a tool line Ping Sweep to discover what IP are really being used by what device. This would help to narrow your search of where there IP are going.

 

[viper62]

Well thats a problem as most of my network clients are XP Pro with SP2 and does not respond to ICMP pings. I am only discovering 27 actual IP's that its saying are alive because of XP's new features. I now have 171 IP's in my scope and it shows that 139 are in use with 32 left being available. I am tempted just to delete the scope and recreate it as this is being a pain in my arse.