-----mack <[EMAIL PROTECTED]> wrote: ----- >Date: 05/05/2008 04:03AM >Subject: [c-nsp] Input queue drops due to backplane congestion > >We have a 6509 with sup720 3bxl running SXF11. >We have a number of 6704-10GE line cards and >A number of 6748-GE-TX line cards all with PFC3BXLs. > >When one (only one) of the 6704 fabric channels peaks at about >80% utilization coming from the fabric we start to >See packet loss on the GigE ports. Even if the traffic >Is confined to one GigE blade. > >We have run a large number of troubleshooting exercises >Including replacing Sup units and line cards. The problem >Is definitely fabric congestion. Our current solution is >Simply to add another line card and move one of the lines >On that fabric channel. > >This is somewhat different from the expected behavior >Which would be drops occurring on the fabric channel counters. > >Has anyone else run into this problem?
Maybe. Another person in the office has a TAC case open for input queue drops on a 6500/sup720 and the TAC engineer came back with this: "With the WS-X6704-10GE blades, ports 1 & 2 belong to one fabric channel and 3 & 4 to another. When traffic is switched between two ports leading to the same asic, you are limited to about 8 Gig per port. If you are pushing this limit, it is possible the flow-control mechanism could induce packet drops. This is a hardware limitation." Regards, Lee _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/