DHCP Problems

It is remotely possible that the infrastructure equipment could be grabbing IP addresses if they are SNMP managed hubs/switches, and programmed to get their IP addresses for management via DHCP. However, since most network admins want to staticallyaddress infrastructure equipment, this is a very unlikely cause. What could be happening is that your WINS server is not releasing NetBIOS name records from the database when clients are logging off, therefore DHCP server is thinking that those IPsare still leased, and the IP addresses in the pool are not available. Flush your WINS database, and all the clients will reregister the next time they log in. They should also receive a valid DHCP-assigned IP address.

Good luck.

When you say you added some hubs, how many hubs are on your network? If you are not using switches you will start to see a degredation in performance if you exceed three occupied hubs on your LAN (by "occupied" I mean hubs populated with workstation connections, and are not simply acting as repeaters). Ethernet is Ethernet, so I don't think that your problem is a result of two different hub manufacturers. My guess is that network traffic could be interfering with the ability of some clients to lease IP addresses from the DHCP server within the timeout period.
You can test my theory by temporarily reducing the number of hubs on you LAN to three. If the problem goes away, you know you have too many hubs. If that is the case, you can by a small switch and connect all your hubs to the switch.

the linksys "hubs" wouldn't happen to be cable modem/dsl routers, would they?

if so, some of these have their own DHCP servers built in. perhaps they're advertising DHCP on the network and confusing the clients?

Chad J. Sutton
Brainbench 'MVP' for Win95 Admin
http://www.brainbench.com

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