can't config dhcp on 2950

Hi,
I'm trying to setup dhcp on my 2950 switch. I'm getting an "% invalid input detected at '^' marker" The ^ points to the "d" in dhcp:

switch(config)#interface vlan 1
switch(config-if)#ip address dhcp
^
"% invalid input detected at '^' marker

This seems kinda weird to me, any ideas out there?
thanks

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Comments

shmish

I thought that I had cleared the configuration when I started (just bought this used switch). However, it looks like the switch still has left-over config info in it. For example, there are a few different vlans on the switch although none of them were assigned to any interfaces. As well, the switch was in VTP client mode.

I had followed this resetting catalyst switches guide from Cisco

to reset the config but forgot to reset the vlan. Is there anything else inside this switch that might be left over from the previous owner, or should I be as new as new can be once I clear the vlan information?

nel

The guide gives you the steps to wipe the config off the switch clean - just as if it had arrived new from the factory. If you get a command similar to the one you initially stated its usually because the IOS doesnt support it. If you want to know what your switch does & does not support use the feature navigator:

http://tools.cisco.com/ITDIT/CFN/jsp/index.jsp

on the cli you could go under int vlan 1 and do a "ip address ?" and it will give the options it will support.

miller811

Why would you want the management VLAN to be assigned via DHCP?
Normally you would assign a static address you could access the device remotely via telnet, etc...
If it is randomly assigned an address that would be tough to do without going to another devices to determine this devices address.

Netwurk

Gotta go with Miller here

You really want to use static IPs for your switches and routers

Unless the new CCENT/CCNA exams test you on how to configure your devices using DHCP?

tndfr

shmish wrote: »

Hi,
I'm trying to setup dhcp on my 2950 switch. I'm getting an "% invalid input detected at '^' marker" The ^ points to the "d" in dhcp:

switch(config)#interface vlan 1
switch(config-if)#ip address dhcp
^
"% invalid input detected at '^' marker

This seems kinda weird to me, any ideas out there?
thanks

from my experience when you get this error it is either the command was not typed in properly or the IOS does not support it.

vlan 1 on a 2950 switch is usually set to a static address, so next time you want to telnet into your switch, you dont go looking for the ip address.
the only reason why i would think you're using this method is when your DHCP server' settings sets the lease to infinite (which is not a very good idea either).

shmish

Thanks guys. I was just trying this as something to work through from the ccna exam guide - just trying out and following an example. I had tried to see if the 2950 supported dhcp but so far my searches only kicked back info about dhcp snooping - whatever that is - with the 2950. I haven't had any problems with configuring a static ip.

cheers
d

miller811

shmish wrote: »

I had tried to see if the 2950 supported dhcp but so far my searches only kicked back info about dhcp snooping - whatever that is - with the 2950.
cheers
d

dhcp snooping is a setting on the switch that restricts or permits DHCP to be pushed through the switch. This is used to prevent a user from plugging a device into the network to hand out addresses instead of the device that is supposed to handout addresses.