Interface Queueing Diagnostics

ccannon88567 · ‎11-18-2008

I have a Cisco 1700 Router which acts as a Gateway to an application in which multiple users from our network access. The application is hosted by another company and so I have no access beyond this router.

The inside area our network is on the side of a 2Mbps Serial Leased Line connection.

The outside is the side adjacent to the companies LAN of the hosted service. This is a Fast E 100Mb.

I am seeing input queueing drops on the interface which connects their server farm and many of my users are complaining of slow connection to this system.

What could be the cause of this high number of input queue drops? Could it be to do with input errors from their switch or is this becasue the buffers are overflowing in the input queue?

Any help would be much appreciated.

FastEthernet0 is up, line protocol is up

Hardware is PQUICC_FEC, address is 000d.bd64.b471 (bia 000d.bd64.b471)

Description: Outside LAN @ **** Site A

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 4w6d

Input queue: 0/75/1062984/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 697000 bits/sec, 252 packets/sec

5 minute output rate 447000 bits/sec, 276 packets/sec

259094706 packets input, 2129952001 bytes

Received 41521197 broadcasts, 0 runts, 0 giants, 0 throttles

890 input errors, 0 CRC, 0 frame, 890 overrun, 0 ignored

0 watchdog

0 input packets with dribble condition detected

371816065 packets output, 2030182445 bytes, 22 underruns

22 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

Serial0 is up, line protocol is up

Hardware is PowerQUICC Serial

Description: *** 2Mb Link ****** to ****** House

Internet address is ********/**

MTU 1500 bytes, BW 2048 Kbit, DLY 20000 usec,

reliability 255/255, txload 87/255, rxload 56/255

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 4w6d

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 7154

Queueing strategy: weighted fair

Output queue: 1/1250/64/7154 (size/max total/threshold/drops)

Conversations 1/97/256 (active/max active/max total)

Reserved Conversations 0/0 (allocated/max allocated)

Available Bandwidth 1843 kilobits/sec

30 second input rate 457000 bits/sec, 349 packets/sec

30 second output rate 699000 bits/sec, 265 packets/sec

372452578 packets input, 2728433827 bytes, 0 no buffer

Received 350486 broadcasts, 0 runts, 0 giants, 0 throttles

8 input errors, 2 CRC, 0 frame, 0 overrun, 2 ignored, 4 abort

220684815 packets output, 212333463 bytes, 2 underruns

2 output errors, 0 collisions, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

DCD=up DSR=up DTR=up RTS=up CTS=up

drolemc · ‎11-25-2008

You can successfully troubleshoot input queue drops while packets constantly arrive in the input queue. You cannot troubleshoot a congestion that occurred in the past. If more than one routed protocol is configured on the interface, first determine the protocol that congests the input queue. Here is the fastest way to do this is.

1. Determine the suspect protocol. Check the CPU utilization in Input processes. To do so, run the show processes cpu exec command.

2. Find out whether packets that congest the input queue are destined for the router, or are forwarded through the router. Run the show interfaces [type number] switching command from exec mode. (Type Full command)

3. If packets are destined for the router, find out which higher-layer protocol congests the input queue. For this, use one of these show traffic exec commands:

For further information click this link.

http://cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a0080094791.shtml#topic3