Changing the VMWare vmnet IP Range when it Conflicts with a VPN on Mac OS X

If you are running both VMWare (in my case VMWare Fusion 5) and a VPN that uses the 192.168.203.0 subnet you will may need to update the ip range that is used for the vmnet.

In my case, vmnet8 was configured to use 192.168.203.0 and so was a VPN connection that I was using.

As a result, if I fired up VMWare first and then attempt to make a connection to the VPN, I could not route to any of the 192.168.203.0 hosts.

Following is what you need to do on a Mac running OS X:

        . Shutdown VMWare Fusion (simply quit the program.  It must stop the vmware_* services)

        . edited: /Preferences/VMware Fusion/networking
                . Updated answer VNET_8_HOSTONLY_SUBNET 192.168.203.0 -> answer VNET_8_HOSTONLY_SUBNET 192.168.247.0
                . /Preferences/VMware Fusion/vmnet8/dhcpd.conf and /Preferences/VMware Fusion/vmnet8/nat.conf will be automatically updated by VMWare with the config change

        . Fire up VMWare Fusion:

# netstat -rn
Routing tables

Internet:
Destination        Gateway            Flags        Refs      Use   Netif Expire
default            10.1.10.1          UGSc           27        0     en0

172.16.19/24       link#8             UC              1        0  vmnet1
192.168.247        link#9             UC              1        0  vmnet8

        . Connect to VPN:

# netstat -rn
Routing tables

Internet:
Destination        Gateway            Flags        Refs      Use   Netif Expire

172.16.19/24       link#8             UC              1        0  vmnet1
192.168.12.156     192.168.12.156     UH              5        0   utun0
192.168.200.120/32 192.168.12.156     UGSc            1        0   utun0
192.168.201        192.168.12.156     UGSc            0       11   utun0
192.168.202        192.168.12.156     UGSc            0        0   utun0
192.168.203        192.168.12.156     UGSc            0        0   utun0
192.168.247        link#9             UC              1        0  vmnet8

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