OSX Internet sharing - how to use own IP subnet and router's DHCP?

I have successfully turned on Internet sharing from System Preferences -> Sharing -> Internet Sharing.

Under Internet Sharing, I selected:
- Share your connection from: AirPort
- To computers using: Ethernet

By default, OSX's natd (NAT Daemon) use the IP configuration from /etc/bootpd.plist. The IP subnet is 192.168.2.xxx. The bootpd shows the following:

Code:

<plist version="1.0">
<dict>
        <key>Subnets</key>
        <array>
                <dict>
                        <key>_creator</key>
                        <string>com.apple.nat</string>
                        <key>allocate</key>
                        <true/>
                        <key>[B]dhcp_domain_name_server[/B]</key>
                        <string>[B]192.168.2.1[/B]</string>
                        <key>[B]dhcp_router[/B]</key>
                        <string>[B]192.168.2.1[/B]</string>
                        <key>lease_max</key>
                        <integer>3600</integer>
                        <key>lease_min</key>
                        <integer>3600</integer>
                        <key>name</key>
                        <string>192.168.2</string>
                        <key>[B]net_address[/B]</key>
                        <string>[B]192.168.2.0[/B]</string>
                        <key>net_mask</key>
                        <string>255.255.255.0</string>
                        <key>net_range</key>
                        <array>
                                <string>192.168.2.2</string>
                                <string>192.168.2.254</string>
                        </array>
                </dict>
        </array>
        <key>bootp_enabled</key>
        <false/>
        <key>[B]detect_other_dhcp_server[/B]</key>
        <integer>[B]1[/B]</integer>
        <key>[B]dhcp_enabled[/B]</key>
        <array>
                <string>en0</string>
        </array>
        <key>reply_threshold_seconds</key>
        <integer>4</integer>
</dict>
</plist>[I]

The thing is, I am using a different IP configuration than the one natd setup, namely in range of 192.168. 1.xxx (note the "1" instead of "2").

My question is: how can I make sure OSX natd use my router's DHCP and IP address instead of it's own?

Looking at the bootpd.plist, can I simply change the following values:
dhcp_domain_name_server -> change to my router's IP address?
dhcp_router -> change to my router's IP address

I am not sure what should I change these though:
net_address -> to my router's IP address, which is 192.168.1.0?
detect_other_dhcp_server -> currently the value by default is 1

 

Shoot, the forum engine keep change the "code" and removed the XML tag, which is what the bootpd.plist have....

 

ok... so just to clear up... because I'm having difficulty knowing for sure what or even why you'd want to do this....

your wanting to use your Mac as a router, but set it up to be like an extension to the main router with the same subnet, so the other computer are basically just like they are connected to the other router....? and your using internal 192.168.x.x? Are you sure there may not be a more simple solution to whatever your main problem is? Not sure its possible to do this, OSX internet sharing is not a very configurable type or full fledged router.

 

I want to acchieve this to , my iphone can only reach the computers also wirelessly conntected to that mac and visa-versa

what my idea is , my router has a subnet (192.168.123.x) but the DHCP is set to 192.168.123.1 till 192.192.168.100
to my mac could hand out from 101 till say 150 ...? no ?

EDIT: didn't work : forgot what NAT stood for