August 7, 2010

Defining new DHCP options

Hello,

I am trying to send out some created DHCP options.
I set up a dhcp3-server on an ubuntu 10.04. I did what is written in man dhcp-options. Namely, i tried to add following lines in dhcpd.conf :

option myoption code 194 = text;
option myoption "helloworld";

I obviously use some casual values for the test.

Then, i edited /etc/dhcp3/dhclient.conf on the client side so that the latter be able to receive the defined option.

My client ask for that option (194) as we can see on the following screenshot :
http://img138.imageshack.us/img138/5197/listeoptions.png

Then, the server send that option :
http://img265.imageshack.us/img265/5784/definedoption.png

However, i don't manage to use the content in a shell script, i think i should do it since

I looked at /etc/dhcp3/dhclient-exit-hooks.d/debug
As it's written in this script, by setting a value on 'yes' we can see different variable used in /sbin/dhcp-script. but my defined option didnt appeared. Indeed, the variable should be $new_myoption (but it doesn't work in /sbin/dhcp-script), i got following lines :

Mon Jun 28 22:42:47 CEST 2010: entering dhclient-enter-hooks.d, dumping variables.
reason='REBOOT'
interface='eth0'
medium=''
alias_ip_address=''
new_ip_address='192.168.2.60'
new_subnet_mask='255.255.255.0'
new_domain_name='test.org'
new_domain_search=''
new_domain_name_servers=''
new_routers='192.168.2.254'
new_static_routes=''
old_ip_address=''
old_subnet_mask=''
old_domain_name=''
old_domain_search=''
old_domain_name_servers=''
old_routers=''
old_static_routes=''
--------------------------
Mon Jun 28 22:42:47 CEST 2010: entering dhclient-exit-hooks.d, dumping variables.
reason='REBOOT'
interface='eth0'
medium=''
alias_ip_address=''
new_ip_address='192.168.2.60'
new_subnet_mask='255.255.255.0'
new_domain_name='test.org'
new_domain_search=''
new_domain_name_servers=''
new_routers='192.168.2.254'
new_static_routes=''
old_ip_address=''
old_subnet_mask=''
old_domain_name=''
old_domain_search=''
old_domain_name_servers=''
old_routers=''
old_static_routes=''
-------------------------

So how could i get access to my defined option ?

Thanks
Regards

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