Hi Leo, the command in global config mode is: ip dhcp excluded-address x.x.x.x this will reserve the ip address for a specific client that is not using DHCP. Thanks, Saleem -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Leo Shen Sent: Wednesday, August 01, 2001 6:25 AM To: [EMAIL PROTECTED] Subject: a question about making cisco 6506 as a dhcp server [7:14465] first,the 6506 is a new one,it's ios is 12.16,so it can control layer2&layer3 with one interface(the old has two interfaces,one is router,another is switch,but the new one only has one interface,it can control both router and switch). now,i have maken the 6506 as dhcp server for about 2 months,the config is : ip dhcp pool vlan210 network 10.2.10.0 255.255.255.0 default-router 10.2.10.254 dns-server 10.2.90.1 ! ip dhcp pool vlan230 network 10.2.30.0 255.255.255.0 default-router 10.2.30.254 dns-server 10.2.90.1 ! ip dhcp pool vlan221 network 10.2.21.0 255.255.255.0 default-router 10.2.21.254 dns-server 10.2.90.1 ...... now,I want to make some special user have special ip address,for instance,one user's mac address is aa-bb-cc-dd-ee-ff,I want that his address will be 10.2.10.101,another user's mac address is 12-34-56-78-90-12,his address will be 10.2.21.202,how can I realize it?except using static address,must via dhcp and 6506'config could someone tell me the command and config? thanks! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=14470&t=14470 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]