I'm hitting the same problem with a bootable 9.1.1.20000-5 .iso on a Unity Connection subscriber install. UCS server is C220M3, using latest 9.1 ova. The same .iso worked fine for a CUCM subscriber install. Will attempt install again with 8.6.2 .i...
I see a router stencil with the same "Si" in the icon. The description is listed "Router w/Silicon Switch". Ref: Silicon Switch Processor, silicon switching.