The Network Monkey

Series (#001) - Dynamically Assigning IP Addresses to Netware Servers
Written by: Jim Huddle CNE, CNE5, CBS, MCSE, send e-mail

For as long as I can remember, which isn't all that long since I've got the memory of a gnat, I've been aggravated because hasn't been a way to dynamically assign an IP address to a Netware server. Now I grant you that most of the time you want a static address on a server, but occasionally you do need more flexibility.

When Netware 5.1 shipped it included a way to do this. They didn't make much noise about it and I only discovered it about a week ago. It’s a bit clumsy to set up, but once it’s configured it works very well.

The key is an NLM named DHCPCLNT. Why would you use this? Well I've got a cable modem at home and I was using a software gateway on my primary workstation to provide my home network with access to the Internet. It worked okay, but it also used a lot of resources and there were some issues with the Netware client. In addition, whenever I had to reboot the workstation, my spouse would look over the top of her monitor and give me a decidedly unpleasant look. The 'Cosmic Muffin' should protect the man who prevents his spouse from getting The Weather Channel site 24 hours a day. In the real world though, if you run Netware, this is a nice way to get Internet access without buying a cable modem router. You can set up both network address translation (NAT) and filtering on a base 5.1 box without installing Border Manager.

Here’s what to do. First you'll need to install a second NIC in the server. Most cable providers only support a few NICs and only on Windows, so once you do this you're pretty much on your own. I used an old Relisys NIC I had laying around. Install the driver and set up the NIC as you would any other one in Netware. Once that’s done open INETCFG, go to Bindings and assign the NIC an IP address. Do this because you can't bind IP to a NIC in INETCFG unless you give it an address. It doesn't matter what you assign it, but it's best to use one of the private addresses set aside for internal networks. Why Novell didn't add that ability when they released the NLM I'll never know. But they didn't, so just live with it. Press Escape and then Expert TCP/IP Bind Options/Network Address Translation. Under Status, select Dynamic Only.

Escape from that and select Protocols and TCP/IP. Make sure IP Packet Forwarding is Enabled and RIP is Disabled. Back out to the main menu and select View Configuration. From there select Protocol Bind Commands. Note the name INETCFG has given the NIC. You'll need the name in the next part.

Escape and exit INETCFG. Either restart the server or enter Reinitialize system from the console prompt. After that enter CONFIG from the console prompt and verify that the second NIC is properly bound with the IP address you gave it.

If everything is good at the console prompt, type EDIT AUTOEXEC.NCF. Since you can't configure DHCPCLNT from within INETCFG, you have to load it separately once initsys.ncf has run. Find the line that loads INITSYS.NCF. Under that, type in LOAD DHCPCLNT NAME=<name from inetcfg bind statement> -inetcfg. The "- inetcfg" tells the NLM to update inetcfg with the setting the NLM pulls from the ISP. Putting this here will load the NLM on every reboot of the server. Escape and save the file.

Back at the console prompt type in the same command. Nothing very exciting happens. Hit Ctrl-Escape and you should see a line that says "DHCP Client INFO SCREEN". Select the number to the left. You will be on screen showing the status of the NIC. If all has gone well you will see the address, subnet mask and gateway assigned by the cable provider’s DHCP server. You'll also see the lease time, when it expires and the DNS servers provided by the ISP. If you check it again after the lease expires you'll see a line telling you the lease was successfully renewed and repeating the information above.

Now you need to set some packet filters to keep the bad guys out. That will have to wait for next time as I'm over my word limit.

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