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Move DHCP server Address Pool range

I want to change the IP range serviced by the DHCP server on my Windows SBS 2003 server.

It is curently leasing addresses in the range 192.168.20.60 to 192.168.20.99.  I want to move the range to 192.168.20.200 to 192.168.20.239.

I would like to make the transition smooth for clients, so my hope is that I can add the new range, then delete the old one.  I'm guessing that I can delete the old one first, then create the new one, but I have a transition period, and I have to document and re-enter all the server options.

I currently have a single superscope containing a single scope.  Actually, I also have a 'test' scope (192.168.21.0 range) that I can't delete because he can't contact the server (there is no such subnet).

Suggestions?
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Don S.
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Just change the address range on the current scope.  No need to delete or add anything.
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localmagic

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When I attempt to do so, it says

DHCP - The specified range either overlaps an existing range or is not valid.
What subnets are you using?
Only 192.168.20.x.   (The 192.168.21.x was just a test)
192.168.20.3 is my server.  
What is your subnet mask?  255.255.255.0? or something else?
subnet mask  255.255.255.0.

Also, Here's the DHCP console:
http://upload2.net/page/download/RmZQC3oQUbTxf32/dhcp.bmp.html
Make sure you remove all the exclusions or other options you have in your current scope that don't match up, or you can't just change the range.  So if you have reserved IP's or something, you will need to get rid of those, then change the range, then put them back in.

The recommendation seems to be to delete the old one and create a new one with the new range you want.  Before you do this, I would recommend changing your lease time to 24 hours and then waiting for the duration of whatever you currently have for your lease time.  This will get all the computers asking for new DHCP information every day.  Then, when all the computers are on for the day, delete your old scope, create the new one, and put in all your settings.  The next day, when the computers come back up and ask for new DHCP info, they will get an IP in the correct range.
I don't have any exclusions or reservations at all.  It's just an IP range, and some DNS options.  
All changes such as this should ONLY be done with the SBS's wizards.  At this point you should reinstall DHCP in order to remove your 192.168.21.x subnet.  Follow the steps outlined at the bottom of this document to do that:  http://sbsurl.com/dhcp

I'm wondering though, why you want to move the scope?  You should be aware that Routing and Remote Access will grab about 8 IP addresses when you run the Configure Remote Access Wizard.

If you have other needs for IP addresses, then you are much better off using DHCP reservations if possible.

Jeff
TechSoEasy
I just saw your comment about "DNS Options"... what are you putting there??

Because again, all of this is configured with the Configure Email and Internet Connection Wizard (CEICW -- linked as "Connect to the Internet on the To-Do list in the Server Management Console).  You should ONLY have your SBS's IP address listed on any internal Network Card as the DNS Server IP.

A visual how-to for that is here:  http://sbsurl.com/ceicw  ... and a full networking overview for SBS is at http://sbsurl.com/msicw

Within that wizard you'll see a "more information" button on each screen that has invaluable help in deciding which options to select.  
Be sure to check those out as well.

Jeff
TechSoEasy
Why did we want to move the scope.... Well, originally, this site was using a Linksys router on 200-239 as DHCP.  We wanted to use SBS instead (for many good reasons).  We made what we thought was a temp scope at 60-99, and disabled DHCP on the Linksys a few weeks back.  Now we would ilke to return the scope to its architected spot.

The DNS options are pretty simple:
003 Router -> 1 (the linksys box)
006 DNS Severs - > 3 (the SBS box)
015 DNS Domain Name -> our domain name

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Jeffrey Kane - TechSoEasy
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The temp scope was just me testing trying to understand why I just could not change the address range myself.

I did more testing today, and discovered that I can change the existing range directly a little bit, e.g., from 60-99 to 60-100.  So maybe there is something about the 200-239 range??  I have IIS using 190-199, but nothing I am aware of above 200.

Why move it?  Well, I did architecture for too many years, and like you, I have defined ranges for servers, hardware/printers, and traditionally leave the >200 for DHCP.

I am frankly a bit wary of trying to use CEICW on the server, concerned that I might (accidentally) break something else in the process.  If possible, I would like to just move the range back up where the picture on the wall says it is (!).

Thanks for the continued help !
What do you mean you have IIS using 190-199?  

And being a bit wary of using the CEICW because it might accidently break something else in the process is completely opposite of the reality.  The reason you use the CEICW is so that you DON'T break one thing by setting another.  

I'm afraid you aren't like me in regards to IP addresses... those aren't MY defined ranges... they are the ones that SBS creates.  It's great that you've done architecture for many years... I never have, and I am keenly aware that if you try to configure an SBS manually you will spend all of your waking hours doing so.  To be leary of using a tool that was specifically designed for the sole purpose of ensuring that the 500 different settings would stay synchronized is like choosing to use a Bic lighter to ignite the pistons of an automobile... because of a concern that the computerized timing of the spark plugs may cause the windshield wipers to wear out.  I know that sounds ridiculous... but honestly, that's what not using the CEICW sounds like to me.

You might find this to be interesting:
http://msmvps.com/blogs/bradley/archive/2004/06/24/8898.aspx 

And this is imperative to read:
http://sbsurl.com/itpro

Jeff
TechSoEasy
Sorry.  I meant Routing and Remote Access.

I'll read the posts (thanks!).  I think I will plan to go onsite this weekend and resolve this.  I'll try to be brave and use the CEICW !
Well, I gave up, and did what I said in the beginning I thought you really had to do.  I just deleted the scope and recreated it from scratch, and it all works.

Thanks for the pointers and help, Jeff.  I did update the additional WINS settings as you suggested.  I looked at using the wizards, but they apparently set the entire range, and then exclude 1-9 for hardware.   I still would have to do stuff manually, and decided just to do so anyway.  The real purpose of this thread was to try to figure out why in the world you can change the ranges in some ways, but not others. I guess we will never know.   I'll send the points your way - thanks again !  
Well, actually it's quite clear to me why you got the error message that "there is no such subnet".  Sorry for not directly answering that for you.  In order to use a different subnet at the same time you were also using the original, would have required you to have two IP addresses on your SBS's NIC, it's DNS, and it's ROUTING table.  A persistent route would have been needed to connect the two subnets so they could communicate with eachother.

All of that, though, is a wonderful exercise to play around with in a test environment... but you should not have created this "test scope" on your live server in the first place.

Jeff
TechSoEasy
Running Windows 2003 servers, I had the same stubborn issue.

> The recommendation seems to be to delete the old one and
> create a new one with the new range

That worked for me. Thanks!

/gustav