DHCP Problem

Ok I am running SBS 2003 and a 2wire router. The router has dhcp disabled or it actualy is not enabled. (I would have thought this was the same) I have setup up a scope for sbs to provide ips for the network. The network only consists of 4 client pcs. It has been running ok until now. Thie problems I seem to be having are as follows.


Although dhcp is disabled at the router if for any reason the clients can get an address from the DC then it seems to get one from the router. I know this because the Ips are not within the range setup in the scope. But sometimes If i can a client to take a ip assigned by the dc it then tries to use the router for dns. Also I have notice I keep getting an exclamtion mark by the scope. I have tried deleting that scope and creating a new scope but the same thing seems to happen after a while. Also the only way I can get a client to get an Sbs assigned ip is by disconnecting the router from the network. I think Im going to become a plumber.
didge1Asked:
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adamdrayerConnect With a Mentor Commented:
From that IPCONFIG /ALL screenshot, it looks like the 192.168.1.4 computer is using the Windows Server for DHCP, which is good.  The problem is that it still has the wrong DNS server.  This is a result of either 1 of 2 things.  

1. The DNS server is hard-coded into the client.  This means that if you go to the properties of the network connection, and then to the properties for TCP/IP, click 'Advanced'.  On the DNS tab, make sure that there is no hard-coded entries.  Also, on the main TCP/IP screen where it specifies to obtain IP address automatically, you'll want to make sure it says to obtain DNS servers automatically as well.

2. Check the scope options for DHCP on the windows server.  Make sure that the scope options specify the server as the only DNS server.  You don't want your Windows server to be handing out 192.168.1.254 as your DNS server.

Once that is all done, goto the client and type "IPCONFIG /RELEASE", and then "IPCONFIG /RENEW", and see if the DNS server has changed.

As far as the 192.168.1.65 computer, its possible that is an active lease that hasn't expired yet.  Run the release/renew on that machine too and see if that helps.
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davy999Commented:
IT could be the lease time, have you tried ipconfig/all then ipconfig /release ipconfig/renew
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Jay_Jay70Commented:
Hi didge1,

ha! been there and done that, i laboured for a drainer! bad times, can you please confirm 100% that DHCP is disabled on the router, what are the addresses that you are getting?

If DHCP has issues on the server and it is disabled on the router, then the addres syou are getting is probably a windows dhcp address

lets narrow down the obvious and go from there
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didge1Author Commented:
Ah Ok

Sbs is set up to give 192.168.0.1 For the DC & 192.168.0.2-192.168.0.5 for the clients. But some times when I do a ipconfig/all on a client pc i get 192.168.0.64 or something thereabouts. It also shows that address in the router so I presumed the router was to blame for assigning it. Also sometimes (When its working properly) The client pc would read something like

Ip address 192.168.0.2
Dns Server 192.168.0.1
Wins Server 192.168.0.1
Deafault  Gateway 192.168.0.254

But then sometimes I get

ip address 192.168.0.2 Which is correct
Dns 192.168.0.254 which is the router  

As i said the only way to get it too appear correct is to unplug the router from the network

I have checked and treble checked the enable dhcp enable is not cheked on the router
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didge1Author Commented:
Also I did wonder about the lease time and set it for 1 year just too see but still get same problem
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Jay_Jay70Connect With a Mentor Commented:
didge1,

this is what i would have setup

statically assign the Server, you should never have a server set to a DHCP address or all sorts of fun arises

set it to say .1

also, your dns should be pointing to the server, assign that within DHCP, add your ISP's DNS as a forwarder under the properties of your forward lookup zone

increase your scope to cater to say 50 addresses

triple check DHCP is disabled on the router, not just not configured those IP's are coming from that router i would put money on it what scope options have you configured

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didge1Author Commented:
Sorry I should have said The server is statically assigned and I have used isp dns as a forwrder I can try and increase the scope.  can u paste screen shots here?
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didge1Author Commented:
Thre is another piece to this puzzle I have 13 Static ips provided by my Isp. I am also using to static ipsfrom my router to another server which provides internet access to guest rooms. This has the static ip hard coded. I also have 1 other static ip assigned to our cctv for remote viewing. Both of these work fine.
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Jay_Jay70Commented:
didge1,

hmm i see i see, but the key point is, when you remove the router from the network, the sbs machine assigns IP's correctly yes! so there must be DHCP running on the router!?!?!

do you have any other DHCP servers on the network?
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didge1Author Commented:
I know that would appear to be the case but the box is not checked when i get back im going to up a screen shot to our website and post the link here.

I guess thats ok to do isnt it ?
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didge1Author Commented:
Ok now I have another major problem

I went into dhcp in order to delete the scope and create a new scope. Now everytime I go into dhcp it just hangs and I cant do anything. I have rebooted several times but to no avail. now whole network is down. Can u repair sbs in the same way as xp pro. (If it comes to that)
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didge1Author Commented:
Ok sorted out DHCP  it has now assigned 3 of client pcs with correct ip addresses and correct dns , wins ect. But 1 of client pcs has been assigned a different address which is not in the address pool of the scope. I also notice that it is pointing to the router for dns and not the DC like all the other client pcs. I have allowed 10 addresses in the scope so its not that. Also If it was that dhcp was enabled on the router, why would 3 client pcs be correct and 1 not. Th eother client pc is also listed in active directory as a client.
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adamdrayerCommented:
Just wanted to add a few things...

you can determine which dhcp server was responsible for providing a particular client computer their address by using "IPCONFIG /ALL" and looking for the "DHCP Server"

also, DHCP is first come, first serve.  If the router responded faster than the DC to the DHCP Lease request, then the router would be the one handing out the lease.

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Jay_Jay70Commented:
apologies for that, i am in Australia and was in bed

where are we up to at the moment?
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didge1Author Commented:
Hopefully u r still awake.

Ok my router seems to be providing addresses . Dhcp is definately not enabled. I have taken some screenshots which can be found below.


http://www.innonlake.co.uk/screen 2.JPG
http://www.innonlake.co.uk/screen%205.JPG
http://www.innonlake.co.uk/screen 1.jpg

For some reason the Server i sshowing up several time in the address leases but the server has a fixed ip.

does any one have any matches and petrol ??
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Jay_Jay70Commented:
lay this out for me

Server IP
router IP
Client Range that you want:

that way i can make some sense of these pics :)
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didge1Author Commented:
Server ip is 192.168.1.1
Router is 192.168.1.254
Range 192.168.1.2-192.168.1.10
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Jay_Jay70Commented:
you have an interesting router config!

i think you need to manually configure that IP to be 192.168.1.254 as currently you have it set to the same IP as the server!

also, do you really need that public route in there - whats it doing?
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didge1Author Commented:
I need public route for fixed ips I.E Remote cctv and another server.

What makes you say the router is configured to 192.168.1.1

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Jay_Jay70Commented:
that pic there.....i may be wrong but it looks like you have selected to assign it the .1 address

http://www.innonlake.co.uk/screen%205.JPG
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didge1Author Commented:
No the router is definately set to 192.168.1.254 I know this because I use this address to get into the interface of the router. The server is definately statically set to 192.168.1.1 although in the address leases it seems to be trying to assign the server some other addresses. If you save the pic u can zoom in and its pretty clear. BTW Ive just come back from Australia 2 weeks ago. What a place !!!
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Jay_Jay70Commented:
its the bomb over here, as for now i am off to bed as i can barely see straight, i will take another look first thing tomorrow morning my friend
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didge1Author Commented:
Ok 3 of the client machines are all correct


ip address 192.168.1.4
subnet 255.25.255.0
Gateway 192.168.1.254
Dhcp Server 192.168.1.1
Dns Server 192.168.1.1

The router is 192.168.1.254
The DC is 192.168.1.1

So no problem there.

But one client is

192.168.1.65   Note The address pool on the DC only goes up to 20
Subnet 255.255.255.0
Dhcp server 192.168.1.254
dns server 192.168.1.254
Gateway 192.168.1.254

So it has to be the router assigning this address But WHY. Dhcp is not enabled in the Router & Even if it was y do the other client pcs take their ips from the DC.

I have done numerous release/renews so its not to do with the lease.

I have removed DHCP from the server and added it again. I have deleted the scope and started a new one.

what more can i do

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didge1Author Commented:
Also Is it normal for sbs to assign addresses to clients that are not in the active directory
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adamdrayerCommented:
yes.  DHCP is independant of Active Directory.  A computer needs to be assigned an IP address before it can get to the point where it authenticates to the server anyway.

I don't think your router DHCP is running.   If you want to verifiy this, temproarily disabled the DHCP service on the server, and then release/renew one of the computers and see what happens.  I have a feeling it will regain the same IP although, technically the DHCP server is not running.

If so,
Try changing the IP address on this .65 machine to a static hard-coded one... then reboot.  Then change it back to "obtain IP address automatically" and reboot again...  

Release/Renew may not be enough to get it to give up the lease.  I thought it might be.
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didge1Author Commented:
Ok with dhcp disabled on the DC i get 192.168.1.66 so the router is giving the address but dhcp Is NOT enabled.
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didge1Author Commented:
Ok and when I start the DHCP Server running on the DC  and do a release/renew on teh client pc taht i just renewed I now get the address assigned by the router. Im pretty sure the router is the major problem but I dont know why
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adamdrayerCommented:
well it sounds like the router's DHCP is active no matter what it says on the screen.  And yes, client computers will always try to use their old addresses, so it will continue using the router as a dhcp server as long as it can.  This is a feature of DHCP.

You may want to call the manufacturer and find out why the router is still leasing addresses even though DHCP is turned off.  Perhahps you should try and update the firmware?
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didge1Author Commented:
Perhaps I should try and hit it with a large sledgehammer
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davy999Commented:
try resetting the router then diable DHCP
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adamdrayerCommented:
I like the way you think didge1! =)
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Jay_Jay70Commented:
mm i think i would have to agree, i cant figure out why in the hell when you disable DHCP that the addresses keep coming, sledgehammer? or a run up, careful balance and aim, and a swift kick through the closest window?
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