Ryan, I have similar problems with 4500s so I keep a close eye on the detailed counters. In particular I watch the transmit drops and also the receive buffer stats. Pauses frames also indicate a problem in our environment and I would expect in some other environments. It's a long output but I have always found it very helpful since the reason for the input/output errors are not always evident in a show interface output.
show int counters detail Port Tx-Drops-Queue-1 Tx-Drops-Queue-2 Tx-Drops-Queue-3 Tx-Drops-Queue-4 Gi5/34 0 0 0 0 Gi5/35 0 0 0 0 Gi5/36 0 0 0 0 Gi5/37 0 0 0 0 Gi5/38 0 0 0 0 Gi5/39 0 0 0 0 Gi5/40 0 0 0 0 Gi5/41 0 0 0 0 Gi5/42 0 0 0 0 Gi5/43 0 0 0 0 Gi5/44 0 0 0 0 Gi5/45 0 0 0 0 Gi5/46 0 0 0 0 Gi5/47 0 0 0 0 Gi5/48 0 0 0 0 Gi7/1 21257797383 0 0 0 show int counters detail .. ... Port Rx-No-Pkt-Buff RxPauseFrames TxPauseFrames PauseFramesDrop Gi4/26 0 0 0 0 Gi4/27 0 0 0 0 Gi4/28 0 0 0 0 Gi4/29 0 0 0 0 Gi4/30 0 0 0 0 Gi4/31 0 0 0 0 Gi4/32 0 107830 0 0 Gi4/33 0 0 346468 0 Gi4/34 0 0 0 0 Gi4/35 0 0 0 0 Gi4/36 0 0 0 0 Gi4/37 0 0 9056 0 Gi4/38 0 0 0 0 Gi4/39 0 0 0 0 Gi4/40 0 0 240746 0 Gi4/41 1548 0 0 0 Gi4/42 0 0 1390048 0 Nick -----Original Message----- From: cisco-nsp-boun...@puck.nether.net [mailto:cisco-nsp-boun...@puck.nether.net] On Behalf Of Ryan West Sent: Thursday, November 05, 2009 4:11 PM To: Gert Doering; Drew Weaver Cc: 'cisco-nsp@puck.nether.net' Subject: Re: [c-nsp] Gigabit Interface Input Errors Hi, > -----Original Message----- > From: cisco-nsp-boun...@puck.nether.net [mailto:cisco-nsp- > boun...@puck.nether.net] On Behalf Of Gert Doering > Sent: Thursday, November 05, 2009 3:39 PM . > > There's not much you can do, except "get a hardware forwarding box" > or "just accept it, and only worry if the errors increase more > frequently". Hopefully I'm not completing high-jacking here, but I have seen similar issues on the 4500 w/WS-X4548-GB-RJ45 line cards. The fabric has 6gbps per slot, so the oversubscription is 8:1. The best tell tale sign that I'm hitting oversubscription are input errors with no CRC or overruns, like below: 30 second input rate 6394000 bits/sec, 719 packets/sec 30 second output rate 722000 bits/sec, 481 packets/sec 770898484 packets input, 957181248327 bytes, 0 no buffer Received 594832 broadcasts (560167 multicast) 0 runts, 0 giants, 0 throttles 282191 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 0 input packets with dribble condition detected 455543646 packets output, 153140605424 bytes, 0 underruns Is there a more systematic approach to detecting this? I've gone through some docs and most useful information is geared toward the 6500, such as http://www.cisco.com/en/US/products/hw/switches/ps700/products_tech_note09186a00801751d7.shtml#ASIC. Currently I have to use a combination of interface statistics and historical Cacti graphs to narrow down over-utilized port ranges. Thanks, -ryan _______________________________________________ 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/ _______________________________________________ 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/