This won't scale. Dedicated KVM needs you as an admin walking to the server, reswitching cables, walking back to the KVM console. Instead, with Out of band managament hw/sw, you spawn a dedicated ethernet and can access it from anywhere. It is a flexibility advantage on the costs of security.
There are boxes that can KVM to multiple servers at a time. You don't need to switch cables. They probably cost similar or less than BMC cards on a per-port basis. You might have to combine with some sort of network boot to set up a machine from scratch.
> They probably cost similar or less than BMC cards on a per-port basis
If you build own servers that's an option to consider but most off-the-shelf servers are sold with BMC (so you pay for it even if don't want it). May be some low end brands sell servers without BMC but if you are looking for relatively reliable hardware you'll likely get a server with BMC.
I was thinking more like just having one IP KVM per server always hooked up to a dedicated management network, basically used exactly like a BMC just with better software.
