[CentOS-virt] VM fails to start on host bootup, but starts fine manually. Why?

[Aleksey Tsalolikhin]

I have 5 VMs on my host.

The first four are setup to start on boot.  But only the first three
end up running.  The fourth has to be started manually.

"Start virtual machine on host bootup" is checked on all four VMs but
the fourth VM does not get started on host bootup.  After the host
boots up, the VM is "Shutdown" state.  If I go into "virt-manager" and
click "Run", it starts just fine.

I looked in /var/log/xen/ and did not see anything related, but I
don't know what I'm looking for.

Any suggestions?

Best,
-at