Can't get an IP Address

[Sillygirl]

I am configuring a win2k server machine, and I have set up DHCP and I cannot get it to issue an address to the clients. All clients are win98se and server is w2kserver. When i assign an address to the client, i can't ping the clients from the server, but they can ping each other. The clients cannot ping the server either. The request times out. Any suggestions would be greatly appreciated.

[PitaBred]

Does the network get out? Can you ping outside addresses from the server? How is the server configured? Are you trying to make it a PDC/BDC, or just a fileserver? Is it acting as the gateway? Post a bit more info about your network, and we might be able to figure something out...

[Sillygirl]

It is a domain server, pdc. The gateway is a seperate router. Did not try to ping addresses outside of the network. It is a DHCP server. It can go out to Browse the internet, though, through the router. Very confusing... <IMG SRC="smilies/frown.gif" border="0">

I appreciate any suggestions.

[Ron Prestenback]

What IP address do the Win98 machines have? (do an ipconfig /all on the Win98 machine). Depending on what it shows, there are a couple of things you want to do.

First of all, check you event log for any error messages. You can solve 80% of your "strange" problems by doing this first.

Next, make sure your DHCP is authorized. Meaning, make sure that you have authorized it from the DHCP screen. Right click on your DHCP server under Administrative Tools, DHCP. If there is option to authorize, then it isn't authorized, and if the option is Unauthorize, then you're fine on that.

Next, make sure you have assigned the right setting in your scope. If you can't ping the computers from your server, that makes me think they aren't receiving IP addresses. The ping request timing out. Is that when you ping the name, IP address or both? Make sure that you check the box on your DHCP configuration screen that says "Always register clients with DNS" or something like that, as Win98 can't dynamically register their own DNS entries on a Win2K Server.

If all clients have a 169.254.x.x address, they aren't getting to the DHCP server, but it would make sense for them to be able to talk to each other. It would also account for the fact that the clients can't ping the server, as I'm sure you don't have the DHCP server set up on a 169.254.x.x address.

Of course, if you have any routers or anything like that between your DHCP server and your clients, they wouldn't be able to contact the DHCP server, as DHCP is done by broadcasting. So, here's your homework: <IMG SRC="smilies/smile.gif" border="0">
1. Check the Event Log on your Win2K server. see if there are any tell-tale entries.

2. Check the DHCP service under administration tools. Make sure your DHCP server is authorized by the DC. You will have to be logged in with a domain administrator account to do this, or local admin if the computer is a stand-alone server.

3. Make sure that you have a DHCP relay agent on the same physical network as the clients, if you're not using bus topology. Otherwise, you must have RFC-compliant routers.

4. Of course, make sure all clients are configured to obtain their addresses from DHCP, i.e. automatically. (I know I probably didn't have to include this one, but I once spent 2 hours troubleshooting a mouse that wouldn't work - reinstalling drivers, adjusting BIOS IRQ's, etc.; come to find out, I didn't have it plugged in <IMG SRC="smilies/wink.gif" border="0">)

5. Finally, from a client computer, do these pings:
ping DHCP server by name
ping DHCP server by IP
ping another client by name
ping another client by IP
ping the ip address of the gateway of the server
ping the external ip address of the server


If you can give me the answer to these 5 question, I can tell you why your DHCP isn't working. <IMG SRC="smilies/smile.gif" border="0"> Good Luck!

[Higg]

Perhaps your router has a DHCP server installed too... see what happens if you shut down your Win-DHCP-Server... does the clients get an IP? Then you have zwo concurrent DHCP servers around - I really don't know who wins then...

[Ron Prestenback]

H166 - neither. They would both assign IP addresses from each of their respective scopes. There would be no way with the current configuration to ensure that clients got their addresses from a particular DHCP server. I don't think, however, that routers can serve as DHCP servers.

[Higg]

Originally posted by Ron Prestenback:
<STRONG>They would both assign IP addresses from each of their respective scopes. There would be no way with the current configuration to ensure that clients got their addresses from a particular DHCP server.
that's just the problem!

I don't think, however, that routers can serve as DHCP servers.
Mine does (AscendPipeline) - and that's the way our world-wide offices (CISCO 7500) are configured!
</STRONG>

[techleet]

Originally posted by PitaBred:
<STRONG>Does the network get out? Can you ping outside addresses from the server? How is the server configured? Are you trying to make it a PDC/BDC, or just a fileserver? Is it acting as the gateway? Post a bit more info about your network, and we might be able to figure something out...</STRONG>

This is totally nit-picking, but Win2k doesn't have PDCs or BDCs. There is only DCs. <IMG SRC="smilies/biggrin.gif" border="0">

[techleet]

It sounds like it could be one of a few things, from the info you gave:

1. Make sure the subnet masks are correctly set. This means if you have a /24 network, make sure you have 255.255.255.0 subnet, and make sure you're on the same network. (As in, if you have a 10.10.10./24 then all achines should be between 10.10.10.2-254 (1 is usually a gateway, 0 and 255 are reserved)).

2. You have a firewall between the server and the clients for GOD KNOWS WHAT REASON.

One more thing... can you ping ANYTHING from the server? Can you ping www.microsoft.com?

[techleet]

Originally posted by Ron Prestenback:
<STRONG>H166 - neither. They would both assign IP addresses from each of their respective scopes. There would be no way with the current configuration to ensure that clients got their addresses from a particular DHCP server. I don't think, however, that routers can serve as DHCP servers.</STRONG>

Actually, I believe when a client sends a request on the broadcast address for a IP, whichever DHCP server gets the request and sends a response first will be the one to serve the ip. I don't think the client would even CARE if it got two responses, unless it happened at EXACTLY the same time which of course is impossible. Also, if you are using a router such as the linksys ones, they have DHCP servers built into them.

[Ron Prestenback]

Hmmm, I thought I'd respoded to this since the last post that I posted, but I am having a little network problem, so I 'm not surprised it didn't go through.

Anyway,
to h166 - as far the router having DHCP, I wasn't really sure about it when I posted that, so thank you for clearing that up for me. I know about network software, network protocols, etc., but I am still pretty clueless when it comes to the hardware aspect. <IMG SRC="smilies/smile.gif" border="0">

to techleet - I was a little ambiguous when I posted there...yes, the client would take whatever response came back first, but DHCP server may not always be the one that gets there first...the client, after receiving aa lease, would then continue to go directly to that DHCP server until 75% of the lease they received from that DCHP was up, which wouldn't happen (the 75% part) unless that client couldn't contact the original DHCP at the 50% mark, as the client should try to renew the lease at 50%.

So if there were two DHCP servers on the network, the only way for them to work together would be to have the same scope configured on each, with inverse exclusion ranges. On DHCP server 1, you would exclude, for example, addresses 50-100, out of scope "192.168.0.2-192.168.0.100", and for DHCP server 2, you would exclude 2-49. You wouldn't know which DHCP server each client is using without looking at their IP address, but if you didn't have the exclusion ranges configured in this way, then there would defintely be conflicting address assignments, using the default configuration on Win2K DHCP server.

[techleet]

Ron,

You're totally right about the two dhcp servers...I forgot about the renewal. <IMG SRC="smilies/smile.gif" border="0">

I don't think that would be the problem though at this point, seeing as how the machines have never gotten an ip. It could be though that they had an ip but then lost it due to that renewal interval, but I believe the default lease time for MS DHCP is 2 weeks, which would be 1 week at 50%. At that rate, the user should have worked for that week's period. But then, it could be that the pcs got served by the router, and THAT lease time could have been 3 days. IMHO the easiest thing to do would be to let the router supply the dhcp requests and just kill the main server, unless the router's dhcp is easy to kill.

I don't mean to sit on the fence here but there's so many damn variables <IMG SRC="smilies/smile.gif" border="0">

Thanks for the input <IMG SRC="smilies/smile.gif" border="0">

[Bryanr]

What router do you have? And which client connection are you using on the clients?