Using the Top N Utility

This chapter describes how to use the Top N utility on the Cisco 7600 series routers.

Note For complete syntax and usage information for the commands used in this chapter, refer to the Cisco 7600 Series Routers Command References at this URL:

http://www.cisco.com/en/US/products/hw/routers/ps368/prod_command_reference_list.html

 

This chapter consists of these sections:

Understanding the Top N Utility

These sections describe the Top N utility:

Top N Utility Overview

The Top N utility allows you to collect and analyze data for each physical port on a router. When the Top N utility starts, it obtains statistics from the appropriate hardware counters and then goes into sleep mode for a user-specified interval. When the interval ends, the utility obtains the current statistics from the same hardware counters, compares the current statistics from the earlier statistics, and stores the difference. The statistics for each port are sorted by one of the statistic types that are listed in Table 61-1 .

 

Table 61-1 Valid Top N Statistic Types
Statistic Type
Definition

broadcast

Number of input/output broadcast packets

bytes

Number of input/output bytes

errors

Number of input errors

multicast

Number of input/output multicast packets

overflow

Number of buffer overflows

packets

Number of input/output packets

utilization

Utilization

Note When calculating the port utilization, the Top N utility bundles the Tx and Rx lines into the same counter and also looks at the full-duplex bandwidth when calculating the percentage of utilization. For example, a Gigabit Ethernet port would be 2000-Mbps full duplex.

Understanding Top N Utility Operation

When you enter the collect top command, processing begins and the system prompt reappears immediately. When processing completes, the reports are not displayed immediately on the screen; the reports are saved for later viewing. The Top N Utility notifies you when the reports are complete by sending a syslog message to the screen.

To view the completed reports, enter the show top counters interface report command. The Top N Utility displays only those reports that are completed. For reports that are not completed, the Top N Utility displays a short description of the Top N process information.

To terminate a Top N process, enter the clear top counters interface report command. Pressing Ctrl-C does not terminate Top N processes. The completed reports remain available for viewing until you remove them by entering the clear top counters interface report { all | report_num } command.

Using the Top N Utility

These sections describe how to use the Top N Utility:

Enabling Top N Utility Report Creation

To enable Top N Utility report creation, perform this task:

 

Command
Purpose

Router# collect top [ number_of_ports ] counters interface { interface_type1 | all | layer-2 | layer-3 } [ sort-by statistic_type2 ] [ interval seconds ]

Enables Top N Utility report creation.

1.interface_type = ethernet, fastethernet, gigabitethernet, tengigabitethernet, port-channel

2.statistic_type = broadcast, bytes, errors, multicast, overflow, packets, utilization

 

When enabling Top N Utility report creation, note the following information:

  • You can specify the number of busiest ports for which to create reports (the default is 20).
  • You can specify the statistic type by which ports are determined to be the busiest (the default is utilization).
  • You can specify the interval over which statistics are collected (range: 0 through 999; the default is 30 seconds).
  • Except for a utilization report (configured with the sort-by utilization keywords), you can specify an interval of zero to create a report that displays the current counter values instead of a report that displays the difference between the start-of-interval counter values and the end-of-interval counter values.

This example shows how to enable Top N Utility report creation for an interval of 76 seconds for the four ports with the highest utilization:

Router# collect top 4 counters interface all sort-by utilization interval 76
TopN collection started.

Displaying the Top N Utility Reports

To display the Top N Utility reports, perform this task:

 

Command
Purpose

Router# show top counters interface report [ report_num ]

Displays the Top N Utility reports.

Note To display information about all the reports, do not enter a report_num value.

Top N Utility statistics are not displayed in these situations:

  • If a port is not present during the first poll.
  • If a port is not present during the second poll.
  • If a port’s speed or duplex changes during the polling interval.
  • If a port’s type changes from Layer 2 to Layer 3 during the polling interval.
  • If a port’s type changes from Layer 3 to Layer 2 during the polling interval.

This example shows how to display information about all the Top N Utility reports:

Router# show top counters interface report
Id Start Time Int N Sort-By Status Owner
-- ---------------------------- --- --- --------- ------- ----------------------
1 08:18:25 UTC Tue Nov 23 2004 76 20 util done console
2 08:19:54 UTC Tue Nov 23 2004 76 20 util done console
3 08:21:34 UTC Tue Nov 23 2004 76 20 util done console
4 08:26:50 UTC Tue Nov 23 2004 90 20 util done console
 

Note Reports for which statistics are still being obtained are shown with a status of pending.

This example shows how to display a specific Top N Utility report:

Router# show top counters interface report 1
Started By : console
Start Time : 08:18:25 UTC Tue Nov 23 2004
End Time : 08:19:42 UTC Tue Nov 23 2004
Port Type : All
Sort By : util
Interval : 76 seconds
Port Band Util Bytes Packets Broadcast Multicast In- Buf-
width (Tx + Rx) (Tx + Rx) (Tx + Rx) (Tx + Rx) err ovflw
------- ----- ---- ----------- ----------- ---------- ---------- ---- -----
 
Fa2/5 100 50 726047564 11344488 11344487 1 0 0
Fa2/48 100 35 508018905 7937789 0 43 0 0
Fa2/46 100 25 362860697 5669693 0 43 0 0
Fa2/47 100 22 323852889 4762539 4762495 43 0 0

Clearing Top N Utility Reports

To clear Top N Utility reports, perform one of these tasks:

 

Command
Purpose

Router# clear top counters interface report

Clears all the Top N Utility reports that have a status of done.

Router# clear top counters interface report [ report_num ]

Clears Top N Utility report number report_num regardless of status.

This example shows how to remove all reports that have a status of done:

Router# clear top counters interface report
04:00:06: %TOPN_COUNTERS-5-DELETED: TopN report 1 deleted by the console
04:00:06: %TOPN_COUNTERS-5-DELETED: TopN report 2 deleted by the console
04:00:06: %TOPN_COUNTERS-5-DELETED: TopN report 3 deleted by the console
04:00:06: %TOPN_COUNTERS-5-DELETED: TopN report 4 deleted by the console
 

This example shows how to remove a report number 4:

Router# clear top counters interface report 4
04:52:12: %TOPN_COUNTERS-5-KILLED: TopN report 4 killed by the console