[ClusterLabs] Pacemaker ocf:heartbeat:IPaddr on different subnets

[Rowan @ Jetboy]

[Ubuntu 14 LTS on VMware ESXi 6; Corosync; Pacemaker 1.1.10]

I'm trying to add a Pacemaker virtual IP address; with it, the gateway, 
and the two VMs it serves on different subnets. I've only done this 
before with all IPs on the same subnet, and I need some help.

I have two VMs on 200.xx.xxx.9 and 200.xx.xxx.10 with the below in 
`/etc/network/interfaces`

     auto eth0
     iface eth0 inet static
         address 200.xx.xxx.9
         gateway 200.xx.xxx.9
         netmask 255.255.255.255

         post-up route add yy.yyy.yyy.1 dev eth0
         post-up route add default gw yy.yyy.yyy.1

and

     auto eth0
     iface eth0 inet static
         address 200.xx.xxx.10
         gateway 200.xx.xxx.10
         netmask 255.255.255.255

         post-up route add yy.yyy.yyy.1 dev eth0
         post-up route add default gw yy.yyy.yyy.1

They're both showing up in Pacemaker, and seemingly communicating OK. 
The bindnetaddr parameters in the two `/etc/corosync/corosync.conf` 
files are:

     bindnetaddr: address 200.xx.xxx.9

and

     bindnetaddr: address 200.xx.xxx.10

respectively.

If everything was on the same subnet, I'd expect to add the virtual IP 
with something like:

     sudo crm configure primitive eth0_virtual ocf:heartbeat:IPaddr 
params ip="200.zzz.z.162" nic="eth0" cidr_netmask="24" 
broadcast="200.zzz.z.255" op monitor interval="10s" timeout="20s"

and while this shows up as resource in crm_mon, it isn't allowing me to 
access one of the VMs via the virtual IP. Clearly there's more to it, 
but what?