Dropped Packets

[snootalope]

Hello

I'm trying to eliminate dropped packets on our offices gateway/router which is a 1751. I can't really tell why the packets are being dropped, but I can see that when I download something from the internet, the amount of dropped packets increases pretty steadily.

This is what I see:

Serial0/0 is up, line protocol is up
Hardware is PQUICC with Fractional T1 CSU/DSU
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 41/255, rxload 62/255
Encapsulation FRAME-RELAY, loopback not set
Keepalive set (10 sec)
LMI enq sent 16971, LMI stat recvd 16971, LMI upd recvd 0, DTE LMI up
LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0
LMI DLCI 0 LMI type is ANSI Annex D frame relay DTE
FR SVC disabled, LAPF state down
Broadcast queue 0/64, broadcasts sent/dropped 0/0, interface broadcasts 0
Last input 00:00:05, output 00:00:00, output hang never
Last clearing of "show interface" counters 1d23h
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 26097
Queueing strategy: dual fifo
Output queue: high size/max/dropped 0/256/0
Output queue: 0/128 (size/max)
30 second input rate 379000 bits/sec, 229 packets/sec
30 second output rate 251000 bits/sec, 180 packets/sec
12927290 packets input, 3429495084 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
12446636 packets output, 2543158055 bytes, 0 underruns
0 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

And it's confusing to me cause I don't see any collisions or output errors. I've tried using the debug packet command to see further into it but that doesn't show me anything. Is there a command I have to use to actually view the debug output?? I didn't think there was.

Anyone know what commands I can use to tell me what packets heading where are dropped and why??

Thanks!
Snooter

 

[vipergg]

You have to make sure you enter "term mon" to see debug messages . Be careful if you are looking at the ip packet flow with debug , this can easily overwhelm the router if you have a large amount of traffic flowing

 

[bierhunter]

I prefer to send debug output to the buffer to view it more easily instead of cluttering up the screen.

Make sure you have logging turned on:

logging buffer 4000 (gives you approx a 4k logging buffer for example)

To view it, just enter:

show log

Also, if you could do a "show buffers" and paste the results here it'd be interesting to look at. With large downloads, you may need to tweak your memory buffers.

BierHunter
CNE, MCSE, CCNP

 

[gconnect]

are you using fast-switching/route-caching 'ip route-cache' or 'policy-maps'? this may take some of the burden off your resources.
what does the 'show proc cpu' while this is occuring to see what the processor usage is like?


*on a sidenote*
my math could be way off as i am about exhausted but it looks like you sent out about 2GB worth of data in about 47hours (# your keepalives every 10sec / 6 = Xminutes / 60 = xhours).

How many users are at that site? Are these 8 hour work days and are the bulk of the data transactions occurring all at the same time (are they using some bad acting SMB based program across the WAN? (or heavy Windows file-sharing)). i usually use 2600XM's for branches (depending on the type of applications they use and of course) if they can afford it because the cpu is better when it comes to heavy transfers.

-gC-