1. The diagram should clearly show the host machines and the expansion chassis and the interconnects between them.
2. We no longer have any Gentoo bootserver or diskless FEs.
3. The "c1lsc" host is in 1X4 not 1Y3.
4. The connection between c1lsc and Dolphin switch is copper not fiber. I don't know how many Gbps it is. But if the switch is 10 Gbps, are they really selling interface cables that have lower speed? The datasheet says 10 Gbps.
5. The control room workstations - Debian10 (rossa) is the way forward I believe. it is true pianosa remains SL7 (and we should continue to keep it so until all other machines have been upgraded and tested on Debian 10).
6. There is no "IOO/OAF". The host is called "c1ioo".
7. The interconnect between Dolphin switch and c1ioo host is via fiber not copper.
8. It'd be good to have an accurate diagram of the current situation as well (with the RFM network).
9. I'm not sure if the 1Y1 rack can accommodate 2 FEs and 2 expansion chassis. Maybe if we clear everything else there out...
10. There are 2 "2GB/s" Copper traces. I think the legend should make clear what's going on - i.e. which cables are ethernet (Cat 6? Cat 5? What's the speed limitation? The cable? Or the switch?), which are PCIe cables etc etc. 

I don't have omnigraffle - what about uploading the source doc in a format that the excellent (and free) draw.io can handle? I think we can do a much better job of making this diagram reflect reality. There should also be a corresponding diagram for the Acromag system (but that doesn't have to be tied to this task). Megatron (scripts machine) and nodus should be added to that diagram as well.