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New Member

Problem DHCP on L3 Switch

Dear Expert and All,

I would like to ask you some quetion on DHCP, i had switch 6509 and all the client provide DHCP

by this switch and never release . I currently 100 user. and i setp DHCP start from 10 to 250. Last time

all the client used from 10-100.So on client ip 20,21,22,23 is doesn't work (i mean now not use this

ip address but it remmaber on switch)so when i take the new computer to plug on the switch it start for 101.

My question: Which command that release ip 20,21,22,23 and the new client renew ip 20,21,22,23?( I mean don't

want the new client catch ip start from 101 because ip 20,21,22,23 is free)

Could you advice Please?

Best Regards,



Re: Problem DHCP on L3 Switch

"set interface sc0 dhcp release" is the command used to release the ip address assigned by DHCP

"set interface sc0" is the command used to assign a new no dhcp ip address.

"set interface sc0 dhcp renew" is the command to renew the DHCP assigned ip address.

For more information on this command refer:

New Member

Re: Problem DHCP on L3 Switch

Dear Hadbou,

thanks you for your advice.

The command that you gave me for OS but my switch is IOS.

Could you give me some command for IOS?

and i would like to know which command that we can release one or two IP not all.:)

Best Regards,


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