Creighton Bill-BCREIGH1 wrote: > > Maybe a dumb observation, but: > Why are input errors and CRC's so dramatically higher on the > ISP side, > wouldn't the constant CRC retransmit requests increase the > utilization?
There's no such thing as a CRC retransmit request. Some protocols do retransmit upon not receiving an ACK, which isn't the same thing as retransmitting upon request. A few protocols, like BYSNCH have a NAK, which might be sort of what you're talking about. The recipient would NAK and the sender would retransmit. Notice that he's using Cisco HDLC, however. Cisco HDLC doesn't have any error correction or retransmissions. It's an extremely simple header with no sequence numbers or ACKs. If a frame arrives damaged with an incorrect CRC, the recipient router silently drops it. The end-node sender (not a router probably) would retransmit and this would result in an equal number of packets out on one side and packets in on the other side of the HDLC link. Just wanted to add this important point which people need to understand for the CCIE written. The real answer about load was provided by the original poster. Load is for output only on a serial link. (I don't think that's true for an Ethernet interace?? Anyone know??) __________________________ Priscilla Oppenheimer www.troubleshootingnetworks.com www.priscilla.com > Excessive line noise or transmission probs? > > -----Original Message----- > From: John Botha (Mnet) [mailto:[EMAIL PROTECTED]] > Sent: Friday, October 11, 2002 3:20 AM > To: [EMAIL PROTECTED] > Subject: RE: Need help with link utilisation [7:55347] > > > The following sh int from both sides: > > Our side: > > MNET4500>sh int s1 > Serial1 is up, line protocol is up > Hardware is HD64570 > Description: 512Kb Internet SOLUTION CCT# 64-63487-11 > Internet address is 196.6.242.90/30 > MTU 1500 bytes, BW 512 Kbit, DLY 20000 usec, rely 255/255, > load 36/255 > Encapsulation HDLC, loopback not set, keepalive set (10 sec) > Last input 00:00:00, output 00:00:00, output hang never > Last clearing of "show interface" counters 1w0d > Input queue: 0/75/0 (size/max/drops); Total output drops: 1720 > Queueing strategy: weighted fair > Output queue: 0/1000/64/1707 (size/max total/threshold/drops) > Conversations 0/96/256 (active/max active/max total) > Reserved Conversations 0/0 (allocated/max allocated) > 5 minute input rate 470000 bits/sec, 59 packets/sec > 5 minute output rate 74000 bits/sec, 55 packets/sec > 20649049 packets input, 2472568997 bytes, 0 no buffer > Received 60233 broadcasts, 0 runts, 0 giants, 0 throttles > 96 input errors, 95 CRC, 44 frame, 0 overrun, 0 ignored, > 12 abort > 18034063 packets output, 3701447186 bytes, 0 underruns > 0 output errors, 0 collisions, 66 interface resets > 0 output buffer failures, 0 output buffers swapped out > 8 carrier transitions > DCD=up DSR=up DTR=up RTS=up CTS=up > > Theirs: > Serial4/4 is up, line protocol is up > Hardware is M8T-X.21 > Description: mnet | B1:TT4:L | 64-63487-11 > Internet address is 196.6.242.89/30 > MTU 1500 bytes, BW 512 Kbit, DLY 20000 usec, rely 255/255, > load 232/255 > Encapsulation HDLC, crc 16, loopback not set > Keepalive set (10 sec) > Last input 00:00:05, output 00:00:00, output hang never > Last clearing of "show interface" counters never > Input queue: 0/75/0 (size/max/drops); Total output drops: 1 > Queueing strategy: weighted fair > Output queue: 0/1000/64/1 (size/max total/threshold/drops) > Conversations 0/32/256 (active/max active/max total) > Reserved Conversations 0/0 (allocated/max allocated) > 30 second input rate 78000 bits/sec, 58 packets/sec > 30 second output rate 467000 bits/sec, 63 packets/sec > 16910473 packets input, 3203937235 bytes, 0 no buffer > Received 0 broadcasts, 177 runts, 7 giants, 0 throttles > 11225 input errors, 11081 CRC, 0 frame, 0 overrun, 0 > ignored, 144 abort > > 19484732 packets output, 1636048060 bytes, 0 underruns > 0 output errors, 0 collisions, 6 interface resets > 0 output buffer failures, 0 output buffers swapped out > 7 carrier transitions DCD=up DSR=up DTR=up RTS=up > CTS=up > --More-- > > > Regards, > > John Botha > E-mail: [EMAIL PROTECTED] > > > -----Original Message----- > From: Magondo, Michael [mailto:[EMAIL PROTECTED]] > Sent: 11 October 2002 09:48 > To: [EMAIL PROTECTED] > Subject: RE: Need help with link utilisation [7:55347] > > John > > Are you sure both interfaces have the same bandwidth configured? > > Michael > > -----Original Message----- > From: John Botha (Mnet) [mailto:[EMAIL PROTECTED]] > Sent: 11 October 2002 09:04 AM > To: [EMAIL PROTECTED] > Subject: Need help with link utilisation [7:55347] > > Hi group > > I have a problem that is currently scrambling my noodle. Our > link to our ISP > shows up as under utilized from a show interface command, most > often sitting > at less than 100/255. I questioned the slow response during > working hours > with one of their engineers, and his interface to us is showing > at running > at greater than 200/255 at the same time that my receiving > interface is > showing less than 100/255. Surely transmitter and receiver > interfaces should > show the same load? > > Any help and/or ideas would be appreciated. > > Regards, > > John > MCSE, CCNA,CCNP,CCDA,CCDP > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=55391&t=55347 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
