On Wednesday, 08/02/2006 at 02:11 EST, Dennis Schaffer <[EMAIL PROTECTED]> wrote: > Please understand that each of my OSA adapters are connected to different > IP subnets (because, my network folks say, that provides optimum > redundancy: completely different network hardware, from the OSA to the > switches/routers, etc., all down the line).
IMO that capability is better provided by trunked switches with backup OSAs connected to each switch. All in a single set of subnets that span physical switches. That moves all the routing decisions down into the switch/router where it belongs. > As a result, I'm not sure the physical redundancy automatically supported > by VSWITCH will really work for my installation. The examples I've seen > with automatic VSWITCH failover seem to assume all OSAs are connected to > the same IP subnet. If the OSA is plugged into a trunk port, then it can carry data for multiple subnets. This is what VLANs are all about. The assumption is that all OSA ports associated with a VSWITCH have access to the same subnets/VLANs. > With that in mind, it seems that moving the network connection of multiple > zLinux systems to VSWITCH moves the routing function from a single IP stack > (VM TCPIP) to each of the zLinux instances. Thats the additional > management and automation I referred to in my previous note. Also, I'm not > sure the combined overhead of running OSPF in each zLinux instance won't be > greater than handling all routing from one stack. > > Am I off-base (at least in regards to this question)? IMO, you don't need dynamic routing in the guest - you need a robust switch and VLAN implementation. Alan Altmark z/VM Development IBM Endicott
