> Does this approach get around the stack limit some way? If we try to put > 800 > machines on a VLAN, will this blow the limit referenced below?
The layer 2 TYPE ETHERNET VSWITCH gets the OSA limits out of the line of fire entirely -- the OSA(s) (note multiple) servicing the VSWITCH just forward frames, acting like a bridge to the VLAN. You can put lots more than 800 guests on a VLAN. I know of people with well over 2000 guests of various types on a single VLAN sharing a VSWITCH. Downside is that unless you have a z10, I don't think you can have a OSA card in layer 3 and layer 2 mode simultaneously, so you can't share a card with a LPAR that requires layer 3 mode. Probably not a big deal for you, as you're likely to push the limits of a card and not want to share it anyway, but YMMV. The limit applies only to device triples directly attached to individual guests, which is a not so hot idea under VM anyway given that VSWITCH exists. It'll also simplify the ability to move virtual machines if IBM ever gets us such a thing -- not tying the adapters to actual physical devices is a Good Thing.
