Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Community Member

Network Latency on Ingress of T1

  I am seeing the receive load of my S0/0/0 interface reaching 90% or higher during normal business hours of an 1841 router in an MPLS network.

The traffic seems to be bursty as the morning is in that 90% or greater range then an hour before noon it subsides, then after around 2pm the receive load hits 90% or greater.

How can I identify the destination of traffic by payload?

Would it be beneficial to add more RAM to this router considering I am seeing drops in the input queue?

Can accounting be turned on and what would it help me find?

Below are some stats for review. Please let me know your thoughts.

MPLS#show
% Type "show ?" for a list of subcommands
GardenCityMPLS#show int s0/0/0
Serial0/0/0 is up, line protocol is up
  Hardware is GT96K with integrated T1 CSU/DSU
  Description:CKID: DS1
  Internet address is
  MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
     reliability 255/255, txload 62/255, rxload 245/255
  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 3d01h
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 71
  Queueing strategy: weighted fair
  Output queue: 0/1000/64/719 (size/max total/threshold/drops)
     Conversations  0/124/256 (active/max active/max total)
     Reserved Conversations 0/0 (allocated/max allocated)
     Available Bandwidth 1158 kilobits/sec
  5 minute input rate 9000 bits/sec, 21 packets/sec
  5 minute output rate 379000 bits/sec, 33 packets/sec
     26148351 packets input, 1592489990 bytes, 0 no buffer
     Received 26449 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     31185959 packets output, 2094069238 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


MPLS#show buffer
Buffer elements:
     1117 in free list (500 max allowed)
     1119542321 hits, 0 misses, 1119 created

Public buffer pools:
Small buffers, 104 bytes (total 50, permanent 50, peak 56 @ 5w5d):
     38 in free list (20 min, 150 max allowed)
     29219726 hits, 32 misses, 17 trims, 17 created
     0 failures (0 no memory)
Middle buffers, 600 bytes (total 26, permanent 25, peak 43 @ 7w0d):
     19 in free list (10 min, 150 max allowed)
     1850609 hits, 6 misses, 17 trims, 18 created
     0 failures (0 no memory)
Big buffers, 1536 bytes (total 50, permanent 50):
     50 in free list (5 min, 150 max allowed)
     5286061 hits, 0 misses, 0 trims, 0 created
     0 failures (0 no memory)
VeryBig buffers, 4520 bytes (total 10, permanent 10):
     10 in free list (0 min, 100 max allowed)
     0 hits, 0 misses, 0 trims, 0 created
     0 failures (0 no memory)
Large buffers, 5024 bytes (total 0, permanent 0):
     0 in free list (0 min, 10 max allowed)
     0 hits, 0 misses, 0 trims, 0 created
     0 failures (0 no memory)
Huge buffers, 18024 bytes (total 0, permanent 0):
     0 in free list (0 min, 4 max allowed)
     0 hits, 0 misses, 0 trims, 0 created
     0 failures (0 no memory)

Header pools:
Header buffers, 0 bytes (total 768, permanent 768):
     256 in free list (128 min, 1024 max allowed)
     512 hits, 0 misses, 0 trims, 0 created
     0 failures (0 no memory)
     512 max cache size, 512 in cache
     538272403 hits in cache, 0 misses in cache

Particle Clones:
     1024 clones, 0 hits, 0 misses

Public particle pools:
F/S buffers, 256 bytes (total 768, permanent 768):
     256 in free list (128 min, 1024 max allowed)
     512 hits, 0 misses, 0 trims, 0 created
     0 failures (0 no memory)
     512 max cache size, 512 in cache
     0 hits in cache, 0 misses in cache
Normal buffers, 1548 bytes (total 768, permanent 768):
     768 in free list (128 min, 1024 max allowed)
     0 hits, 0 misses, 0 trims, 0 created
     0 failures (0 no memory)

Private particle pools:
Serial0/0/0 buffers, 1536 bytes (total 64, permanent 64):
     0 in free list (0 min, 64 max allowed)
     64 hits, 0 fallbacks
     64 max cache size, 32 in cache
     1156422135 hits in cache, 0 misses in cache
FastEthernet0/0 buffers, 1552 bytes (total 512, permanent 512):
     0 in free list (0 min, 512 max allowed)
     512 hits, 0 fallbacks
     512 max cache size, 256 in cache
     1431404774 hits in cache, 0 misses in cache
FastEthernet0/1 buffers, 1552 bytes (total 512, permanent 512):
     0 in free list (0 min, 512 max allowed)
     512 hits, 0 fallbacks
     512 max cache size, 256 in cache
     256 hits in cache, 0 misses in cache


MPLS#


MPLS#show ver
Cisco IOS Software, 1841 Software (C1841-ADVSECURITYK9-M), Version 12.4(3i), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Wed 28-Nov-07 18:48 by stshen

ROM: System Bootstrap, Version 12.4(13r)T, RELEASE SOFTWARE (fc1)

MPLS uptime is 28 weeks, 2 days, 15 hours, 24 minutes
System returned to ROM by power-on
System image file is "flash:c1841-advsecurityk9-mz.124-3i.bin"


This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html

If you require further assistance please contact us by sending email to
export@cisco.com.

Cisco 1841 (revision 7.0) with 234496K/27648K bytes of memory.
Processor board ID
2 FastEthernet interfaces
1 Serial interface
1 Virtual Private Network (VPN) Module
WIC T1-DSU
DRAM configuration is 64 bits wide with parity disabled.
191K bytes of NVRAM.
62720K bytes of ATA CompactFlash (Read/Write)

Configuration register is 0x2102

Everyone's tags (4)
2 REPLIES
Hall of Fame Super Gold

Re: Network Latency on Ingress of T1

You paclet drop rate is extremely small, hence you don;t really have a problem beside user perceived performances.

Search for "netflow". These is also a feature to see traffic within the router.

No addiotnal RAM will help at all.

Re: Network Latency on Ingress of T1

If you want to see what is going where, configure net flow top-talkers.

Sent from Cisco Technical Support iPad App

590
Views
0
Helpful
2
Replies
CreatePlease to create content