Hi, I'm attempting to set up a virtualized "farm" of servers under VirtualBox. I'll need to create a bunch of VMs, and I don't want to have to manually set their hostname and IP address, so a DHCP solution is attractive. The DHCP server built into VirtualBox doesn't allow us to either (a) dynamically update the DNS, or (b) pre-bind MAC addresses to IP addresses, so I've been looking at using dnsmasq.
I'm running dnsmasq on the (Mac OS X 10.6) host, with the following config: interface=vboxnet0 bind-interfaces dhcp-range=vboxnet0,192.168.56.100,192.168.56.200,255.255.255.0,1h dhcp-leasefile=/usr/local/etc/dnsmasq.leases vboxnet0 is the "host-only" network adapter set up by VirtualBox to allow communication between the host and guest. The guest VMs (Debian lenny) are set up with host-only network adapters, and the following in their /etc/network/interfaces: auto lo eth0 iface lo inet loopback iface eth0 inet dhcp With this setup, I can happily send TCP traffic in both directions (between host and guest VMs). I can't quite get dnsmasq working, though! Running (dnsmasq) in debug mode, when I run "dhclient" on the guest VM I can see the DHCPDISCOVER packet come in, and the DHCPOFFER go back out: dnsmasq: started, version 2.55 cachesize 150 dnsmasq: compile time options: IPv6 GNU-getopt no-DBus no-I18N DHCP TFTP dnsmasq-dhcp: DHCP, IP range 192.168.56.100 -- 192.168.56.200, lease time 1h dnsmasq: reading /etc/resolv.conf dnsmasq: using nameserver 10.112.121.75#53 dnsmasq: using nameserver 10.112.121.55#53 dnsmasq: read /etc/hosts - 10 addresses dnsmasq-dhcp: DHCPDISCOVER(vboxnet0) 192.168.56.103 08:00:27:7c:fc:c5 dnsmasq-dhcp: DHCPOFFER(vboxnet0) 192.168.56.103 08:00:27:7c:fc:c5 dnsmasq-dhcp: DHCPDISCOVER(vboxnet0) 192.168.56.103 08:00:27:7c:fc:c5 dnsmasq-dhcp: DHCPOFFER(vboxnet0) 192.168.56.103 08:00:27:7c:fc:c5 ... Unfortunately, the guest never sees the DHCPOFFERs, and eventually gives up in disgust. It seems like the DHCPOFFER packets aren't making it back onto the host-only network (vboxnet0). Help! Any ideas how I might get dnsmasq working effectively? Is this more likely to be a problem with dnsmasq, or with VirtualBox's networking? How might I debug it further? -- cheers, Mike Williams
