thirdbIT

VMware Fusion is a wonderful thing. I am happily running three Linux instances at once under my MacBook with 4GB of RAM (though, as best I can tell, the mobo can actually only address 3GB of RAM).

One glitch that was driving me crazy, though, was that it seemed like DHCP leases were being allocated flakily to the guest machines. When you’re doing database replication, you can’t have master/slave IP addresses changing all the time. (And you certainly don’t want two machines with the same IP address!)

Some digging around turned this up. I don’t remember exactly where — I believe snippets of it were in an official VMware forum — but it was harder to find than it should have been. Hence my posting, to add another path to help those who need it.

On OS X, the file you need to change should be in /Library/Application Support/VMware Fusion/vmnet8/dhcpd.conf. (vmnet8 is the virtual interface for NAT networking in the guest machines.) You should have a subnet clause in it already like this:

subnet 172.16.253.0 netmask 255.255.255.0 {
    range 172.16.253.129 172.16.253.254;
    option broadcast-address 172.16.253.255;
    option domain-name-servers 172.16.253.2;
    option domain-name "localdomain";
    option routers 172.16.253.2;
}

Now, for each virtual machine, set up a new host clause, e.g. :

host ubuntu64-vm {
    hardware ethernet 00:0F:FF:EF:00:00;
    fixed-address 172.16.253.20;
}

Be sure to assign an IP address (fixed-address) outside the range specified in the subnet clause at top.

Get the Ethernet MAC address from ifconfig eth0 inside the guest machine, or from ~/Documents/Virtual Machines/GUESTMACHINENAME/GUESTMACHINENAME.vmx (it’s the line with ethernet0.generatedAddress).

Finally, restart the requisite VMware daemons by running

sudo "/Library/Application Support/VMware Fusion/boot.sh" --restart