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Slackware 8.0 DHCP sending wrong subnet.

By phil.hall ·
Hello all, we (that is to say, the company for which I am employed)
are having an interesting situation that I hope someone here has seen
before and can assist us with.

Thanks in advance for any help.

OK, here's the deal: recently we replaced our previous DHCP server
with a new one. The old server was NetWare Border Manager (version
3.x) and the new one is Slackware Linux 8.0 (with the default DHCP
daemon installed). The Kernel was upgraded to 2.4.17.

The problem we're having is this: some computers attached to our
network are receiving (or have received) incorrect information from
the DHCP server. The IP Address range is fine (172.16.x.x) but the
Subnet Mask, which should be is being set to

Has anyone seen this before and know how to rectify this? The
workstations that receive the DHCP leases are all Windows 95/98/2000.
The workstations that are receiving the problematic netmask are only

Here's the relevant portion of our dhcpd.conf:

subnet netmask {
option routers;

So you see, this should be fine. Basically, give each client a unique
IP Address between and, inclusive; excepting for
Static IP Addresses (servers).

Yet, this setup is producing the error as indicated above.

Any ideas?
Thanks in advance.

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Slackware 8.0 DHCP sending wrong subnet.

by phil.hall In reply to Slackware 8.0 DHCP sendin ...

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Slackware 8.0 DHCP sending wrong subnet.

Hmm you rejected my answer so I can't add comments which help answer your question but in rejected Answer 3 you seem to be sure your DHCP server is sending the wrong subnet mask out where before you didn't have it narrowed down to that. You didn't answer Is "Obtain an IP address automatically" selected on the IP Address tab in the TCP/IP Properties dialog box for the NIC of the Win clients or disable their ability to do so with Regedit so I will assume those clients aren't doing that. Since this is Novell do those clients have autoexec.ncf and what is in there? The incorrect subnet mask maybe? I would blame the client first not the daemon unless you have a concrete reason to think so that you haven't said since DHCP is a pull protocol and your other machines are fine. I would look at the packets for Discover, Offer, Request, and ACK from those bad clients to the DHCP server. You could also check HKEY_ LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Vxd\Dhcp\Dhcpinfoxx and see if it isgetting the bad mask there.

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