Unable to communicate to FreeNAS jails

Years ago I set up ClearOS 5.2 as my home gateway. Recently the PC it was running on died, so I replaced it and installed the latest ClearOS 7.

I also have a FreeNAS box inside the network, which uses FreeBSD "jails" in which to run its Plugin services such as Plex, Transmission, etc. (I know ClearOS has these services as well, but it makes more sense to me to run them on the same box that the files associated with them are stored.) For the uninitiated, a jail is a kind of faux-VM inside the operating system, with its own IP address and filesystem. Nothing has changed on the FreeNAS box.

In my network, I have the following:

ClearOS gateway - 192.168.1.1
FreeNAS - 192.168.1.10
Plex jail (within FreeNAS) - 192.168.1.11
Transmission jail (within FreeNAS) - 192.168.1.12
DHCP range - 192.168.1.100-254


With the new ClearOS gateway, most everything works, except one aspect of networking that was not an issue before. I cannot establish communication between the gateway and any of the jails, or vice versa. I can PING the jails from any PC on my network (static or DHCP), and the jails can PING them back: but the ClearOS gateway is unreachable. This obviously means that I can no longer use Transmission, since it cannot route traffic to and from the internet without the ability to communicate with the gateway.

Any ideas as to what might be different between 5.2 and 7 in this respect? Thanks.