Hi there,
I know that folks will use OME in a WAN environment, but it depends a lot on the WAN speed. I've heard 6mbs or better may work. But you really have to test it.
Some of it depends on the protocols used. Are you able to use WSMan (11 or 12G servers?). SNMP may not be reliable on a WAN, so you can set your status polling to be more frequent. You can also pull the hardware logs remotely via OME.
Maybe if you can provide a bit more details about the network and the type of servers, we could come up with something to try.
Best regards,
Rob