General discussion

WinXP doesn't release DHCP info properly???

I'm the network assistant at a small college, and we've noticed a trend with Windows XP boxen. It seems that two strange behaviors are occuring with some frequency:

1. Many students report that their connection stops working. When they restart the computer, it retains expired DHCP information, rather than releasing it and getting a new lease. All that is required is to unplug the network cable so that Windows resets the device, and they work again, automagically.

2. Other students report the same thing. Upon investigation, their ports have been marked unusable in the DHCP tables. The reason this happens is that there is an IP conflict, and our theory is this: that Windows, failing to release the old IP, requests a new lease. The DHCP server pings the IP before it gives it out, but the ping comes back as active because Windows has failed to release the IP address. Hence, DHCP detects a conflict and marks the port unusable.

Has anyone else dealt with similar problems, and, if so, how did you solve it? I noticed that SP1 fixes a few DHCP issues, but this didn't seem to be among them. Any help, &c. Thanks.

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Re:WinXP doesn't release DHCP info properly???

1. The same complaint was noted for the other versions of Windows.

You can use any number of methods to have it forcefully release the IP info.

2. Some install firewalls that block pings. What happens next is that the DHCP server can't check to see that the IP is in use. Your complaint is typical and I wish you the best of luck educating that blocking pings is going to cause issues in some enviroments.

Bob

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Re:WinXP doesn't release DHCP info properly???

BTW, another recent rash of this involved the users setting the IP information so they could run server software or find their PC by IP.

You have to visit the computer often to find out that they did that.

Bob

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Re:Re:WinXP doesn't release DHCP info properly???

We usually do visit the computer physically. It's a small enough campus that we can do that. I've separated out the incidents of people running local firewalls or setting their own IP numbers. The issue at hand remains as was initially described: DHCP is set up properly, but rebooting fails to refresh the information. A physical disconnection is necessary. (Plus, even if they were setting static IPs, physically disconnecting the NIC wouldn't fix that. It *does* fix our problem.)

What we are seeing is an XP-specific issue, too; we have not experienced this in previous years, nor are we experiencing it this year with non-XP boxen.

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Re:Re:Re:WinXP doesn't release DHCP info properly???

The same issue occured in other versions.

Use the Microsoft Knowledge Base about releasing IP information. The KB is over at http://support.microsoft.com

The issue is not XP specific and you'll find the answers from NT/2000 will be helpful.

Bob

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Re:Re:Re:WinXP doesn't release DHCP info properly???
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Re:Re:Re:Re:WinXP doesn't release DHCP info properly???

While I'm sure that would work for some people, I'm not terribly confident in the abilities of many of our less tech-savvy students. (Some of them have called us asking to hook their Kazaa up properly. Other use phone cords and wonder why they don't work.) We may make this recommendation, but I don't expect that it would work for the vast majority of the campus.

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How long is the lease?

I just reviewed some articles and the question I have is how long is the lease?

When you hand out that IP, you may have given the lease for 7 or more days. As such, it's correct that the machine doesn't have to release it on shutdown.

Bob

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Re:How long is the lease?

The lease is 45 minutes.

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Re:Re:How long is the lease?

Is the XP client noting such?

I came across this once before and the DHCP server wasn't to 'spec' with what Microsoft noted.

Have you try the tool David mentioned as well as the IPCONFIG /RELEASE all on shutdown?

Bob

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Re:Re:Re:How long is the lease?

I have not had a chance to try the NT IP tool. However, ipconfig /release does not solve the problem. I can't recall if the client is properly noting the lease time; I'll keep that in mind with the next box I service, though.

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Re:Re:Re:Re:How long is the lease?

The IP Tool will not work if ipconfig /release in Command Prompt doesn't work!

This may point towards a H/W issue.

I recalled having to either replace the NIC or swap it to another PCI slot to overcome this.

If you have a spare NIC try swapping for a new one?

Whilst you're at it might also change the patch cable on the affected PCs just in case it's a deffective cable.

Good luck.

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Re:Re:Re:Re:Re:How long is the lease?

We always test the cables, so that's not an issue. It seems to be a pretty widespread problem, so I'm guessing it's not hardware, either, but it may be with some people -- we've had a few who keep having the problem a lot. Unfortunately, we're not allowed to open their cases, so I can't install a new NIC, but I will run diagnostics on their cards in the future. Thanks!

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Re:Re:Re:How long is the lease?

I have not had a chance to try the NT IP tool. However, ipconfig /release does not solve the problem. I can't recall if the client is properly noting the lease time; I'll keep that in mind with the next box I service, though.

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Are you reporting that release doesn't work?

Microsoft would want a trouble report on that.

I use that a lot and that does release the IP, even up on the DHCP server.

Something isn't being said here. More clues are needed.

Bob

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Re:Are you reporting that release doesn't work?

Sorry, my mistake. ipconfig /release *does* work, but ipconfig /renew doesn't, until I unplug and replug the cable. Then it auto-renews, but I can also release/renew to my heart's content. Before I physically toggle the connection, though, all attempts to renew time out.

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That effect was noted back in Windows 2000...

The issue revolved around the network card driver being not ready for prime-time.

I hate to keep asking, but you didn't reveal what happens on the ipconfig /renew. In gritty detail, tell about "doesn't".

Bob

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Re:Re:Are you reporting that release doesn't work?

It times out. Interestingly, in most of these cases, attempts to put in a static IP also fail; no network comes up, even if I configure in a correct static IP. In some cases, however, turning off DHCP, configuring for a static IP, and then turning DHCP back on will solve the problem.

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Re:Re:Are you reporting that release doesn't work?

It times out. Interestingly, in most of these cases, attempts to put in a static IP also fail; no network comes up, even if I configure in a correct static IP. In some cases, however, turning off DHCP, configuring for a static IP, and then turning DHCP back on will solve the problem.

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Re:Are you reporting that release doesn't work?

Sorry, my mistake. ipconfig /release *does* work, but ipconfig /renew doesn't, until I unplug and replug the cable. Then it auto-renews, but I can also release/renew to my heart's content. Before I physically toggle the connection, though, all attempts to renew time out.

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Re:Re:Re:How long is the lease?

I have not had a chance to try the NT IP tool. However, ipconfig /release does not solve the problem. I can't recall if the client is properly noting the lease time; I'll keep that in mind with the next box I service, though.

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Re:WinXP doesn't release DHCP info properly???

I have had the same problem and have had to use the same remedy. I did not know the technical reason but only by turning off my DSL connection modem and turning it back on could I restablish my connection.Rebooting was useless. I am running Win XP with Zonealarm.
David

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Re:WinXP doesn't release DHCP info properly???

<b>'owdy,</b>


<b>Please read</b> the Microsoft Developer Network (MSDN) article, <A HREF='http://support.microsoft.com/?id=313896'TARGET='resource window'STYLE='text-decoration: underline'>DHCP Clients Cannot Obtain an IP Address from the DHCP Server (313896)</a>.

</UL></UL><MARQUEE width=300 BGCOLOR=white WIDTH=300 HEIGHT=35 DIRECTION=left><FONT SIZE=+0 COLOR=009900><b>Good luck,</b></MARQUEE></FONT>

<IMG SRC='http://home.mindspring.com/~bgaston2/stuff/BG.gif' ALT='You may E-mail me using: bgaston2@mindspring.com' height='20' width='100' align=ABSCENTER>

Pardon ma ACKsent, ah'm frum Austin, Tex_As, USA

<FONT SIZE=1 COLOR=CC0099> ....its been my policy to view the Internet not as an 'information highway,' but as an electronic asylum filled with babbling loonies.</FONT>

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Bill are you sure this applies? It's for WiFi DHCP Client?

'...When a Windows XP 802.1x wireless Dynamic Host Configuration Protocol (DHCP) client times out or roams between access points, the client may not be able to obtain IP addresses from the DHCP server. This behavior may be intermittent...'

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NT - Not at all -- it just covers a lot of interesting ground.

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NT -or it just covers a lot of interesting airspace.

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NT - I guess some days it just isn't worth trying to help.

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NT - I wouldn't say that.

/

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Sorry Bill. Didn't mean to upset you....

just pointing out relevance so as not to confuse the member with the problem to resolve...
IMO, links should try and point him towards the general/right direction?

Wink

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Re:Sorry Bill. Didn't mean to upset you....

Actually, we've got a student having WiFi problems, too, so I've already read the article in question. Happy

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NT - 'ou didn't David. 'Hot air' is something else though.

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