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New Member

Systems don't get DHCP

I have replaced 3com switches with a Cisco 4000 switch. This is an AVVID implementation so I have the Auxilery power supplies. This problem did not exist when the network was on the 3com switches. Windows 98 systems when booting do not get their DHCP response within the timeout period, but will get it when forced to renew. Windows 2000 and XP systems don't have the problem. Vlan 1 is where the subnet resides and the default route is set to the firewall that is also providing DHCP. Spanning tree is shut off completely. The computers are shut off every night and the lease on DHCP is 1 hour. The computers are plugged into the IP Phones. I also have input this into the switching catagory. Any ideas?

New Member

Re: Systems don't get DHCP

Make sure you have set spantree portfast on all the ports that you have hosts connected that use DHCP.

Here's the command:

set spantree portfast enable

Note: make sure you do not set portfast on any port that is connected to another switch or any device that is running spanningtree protocol.