Miguel Delapaz wrote on 08/02/2006 01:00:40 PM: > > Dennis, > > When more than one path to a destination exists, and they have the > same "cost" (as defined by the routing protocol), z/VM TCP/IP will > round robin packets to that destination through the available paths. > For static routing, this behavior is controlled by the > EQUALCOSTMULTIPATH parameter on the ASSORTEDPARMS statement. For > dynamic routing (MPRoute), this behavior is always enabled. z/VM > TCP/IP only does this on a per-packet basis (we are looking other > options for the future). A "hack" you can use to get around this, > in your case, is to modify the COST0 parameter on one your > OSPF_INTERFACE statements. By forcing the links to have different > costs, MPRoute will only use the path with the lowest total cost, > and will no longer round-robin the packets. In the event of adapter > failure, MPRoute would fail-over to using the higher cost path. > > Regards, > Miguel Delapaz > z/VM TCP/IP Development > >
Miguel, My network guy doesn't like that option very much, although we understand thats the way TCPIP currently works. He asks: "Most network equipment supports either selecting one of the paths from an ECMP environment based on an address hash or round-robin. Apparently IBM doesn't support anything other than round-robin??? Are there any plans to enhance this in the future?" Are there any enhancement plans in this area? Would a direct VSWITCH connection to the zLinux server (running RHEL AS 4) be more flexible in this area? In other words, is the Linux TCP/IP stack (w/ Zebra/OSPF) be more flexible? Miguel, I don't really expect you to answer this part of the question because you're not supposed to be a Linux expert; maybe someone else on the listserve would know. But, if you do ... Thanks, Dennis
