threshold for input error

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Feb 1st, 2008
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Is there a threshold (in percentage) for input error on the ethernet interface. The inut error are generally increasing due to overrun. if the percentage is less than .1% in 24 hours is this a real problem? If someone can point me to a documentation that would be great.



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paolo bevilacqua Fri, 02/01/2008 - 07:58
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Is not a problem as the number is still small, anyway is symptom that the router is not working properly.

Which router is that ? What is the interface the packets go out? Which features are enabled ?

rana_beech Fri, 02/01/2008 - 08:15
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Hi, this router has a 1M connectivity on the serial and is using CBWFQ. it is a 1721. cpu is less than 20% at all times. The % is in fact much lower than I mentioned in my earlier post.

#show interface fa0

FastEthernet0 is up, line protocol is up

Hardware is PQUICC_FEC, address is 000d.bcc0.3840 (bia 000d.bcc0.3840)

Description: AK_NEt

Internet address is

MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Full-duplex, 100Mb/s, 100BaseTX/FX

ARP type: ARPA, ARP Timeout 04:00:00

Last input 00:00:00, output 00:00:00, output hang never

Last clearing of "show interface" counters 1w3d

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

30 second input rate 109000 bits/sec, 26 packets/sec

30 second output rate 66000 bits/sec, 23 packets/sec

55489952 packets input, 1802339287 bytes

Received 4967488 broadcasts, 0 runts, 0 giants, 0 throttles

95 input errors, 0 CRC, 0 frame, 95 overrun, 0 ignored

0 watchdog

0 input packets with dribble condition detected

49210614 packets output, 577143256 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 babbles, 0 late collision, 0 deferred

0 lost carrier, 0 no carrier

0 output buffer failures, 0 output buffers swapped out

Danilo Dy Fri, 02/01/2008 - 08:03
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input error specially accumulating very fast is a concern. What device and model this is on?

Cisco states the following about input errors of the overrun variety:

Description: The number of times the receiver hardware was unable to hand received data to a hardware buffer.

Common Cause: The input rate of traffic exceeded the receiver's ability to handle the data.



rana_beech Fri, 02/01/2008 - 08:21
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hi, 1721 is the hardware. could this happen when there is a burst of traffic on the LAN but the output queue on the serial does not have enough buffer. I can also see interface reset on the FE interface at times.

How can I verify this?




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