DHCP scope on 3560

[Andy White]

Hello,

Our remote office's all use Cisco 3560's and get their DHCP requests serviced by these switches, the scope currently is something like this:

ip dhcp pool Office1

   network 172.30.80.0 255.255.255.0

   domain-name gb.vo.local

   default-router 172.30.80.1

   dns-server 192.168.21.10 192.168.21.11 (DNS servers based in HQ over WAN)

We now need to add the following, but I'm not sure the Cisco switches can do this as a these settings do work from a Windows DHCP server:

I

option name being used already:

003 Router - users gateway IP (on Cisco it's default-router)

006 DNS Servers - Users DNS IP's (on Cisco it's dns-server)

015 DNS Domain name - DNS forward look up zone (on Cisco it's gb.vo.local)

I just need to add the following:

option name:

066 Boot Server Host name

067 Bootfile name

is this possible?

[cadet alain]

Hi,

in your scope use the option  66 ascii and option 67 ascii commands

Regards.

Alain.

[lal.antony]

Hi Andy,

Yes it is possible.

To implement Option 66: Boot Server Host name, just use the following command.

option 66 ascii “server_nam”e !This is if you want to use Server Name

OR

option 66 ip IP_ADDRESS !This is if you want to use Server IP Address

To Implement Option 67: Boot File Name, just use the following command.

option 67 ascii "FILENAME

Cheers

Lal Antony

CCNA, CCNP

www.lalantony.com

[Andy White]

Might be a silly question, why wouldn't I just use:

Option 66 ip

Option 67 is a name of a boot file name called  box2000.0" 

Just tried the first line and it was accepted but not the second:

SWITCH1(dhcp-config)#option 67 ascii box2000.0

% DHCP does not allow raw option 67.

I'm not sure what the ascii is.

Thanks

[lal.antony]

Hi Andy,

Can you please let me know your IOS level for the switches. I believe Option 67 is support on the latest IOS. If you let me know I can check it is the problem. Meanwhile I will find out which IOS version started supporting this option.

Regarding using the IP, This is fine given the DHCP clients can accept this as IP. Some DHCP clients can't get option 66 in IP only accept it as acsii.

hope that helps.

Cheers

Lal Antony

www.lalantony.com