Booting the Supervisor Engine III from Flash

To boot from a Flash device, use the following command:

boot [device][image name]

Note	If you do not specify an image file name, the system defaults to the first valid file in the device.
	Remember that file names are case sensitive. Use the show flash command to view the Flash
	files. The device can be the local Supervisor Engine’s Flash memory or a TFTP server.
Related solution:		Found on page:
Using the show flash Command on a Set/Clear		493
Command−Based IOS

Setting the Boot Configuration Register

You can set the boot method for the switch manually using the boot field in the configuration register. This command affects the configuration register bits that control the boot field, similar to the way a router does. There are three syntaxes for the set boot config−register boot command:

∙rommon—This syntax forces the switch to remain in ROM Monitor mode at startup.

∙bootflash—This syntax causes the switch to boot from the first image stored in Flash memory.

∙system—This syntax allows the switch to boot from the image specified in the BOOT environment variable.

To set the configuration register boot field, use the following command in Privileged EXEC mode:

set boot config−register boot {rommon|bootflash|system} [module number]

Here’s an example of using the command:

Seans5002> (enable) set boot config−register boot rommon 1 Configuration register is 0x140

ignore−config: enabled console baud: 9600 boot: the ROM monitor Seans5002> (enable)

Configuring Cisco Express Forwarding

You configure CEF in the Global Configuration mode. The following commands for configuring CEF and dCEF are available on the Cisco 8500 and 12000 GSR series.

Enabling CEF

To enable standard CEF, use the following command:

ip cef

Disabling CEF

To disable standard CEF, use the following command:

no ip cef

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Enabling dCEF

To enable dCEF operation, use the following command:

ip cef distributed

Disabling dCEF

To disable dCEF operation, use the following command:

no ip cef distributed

Warning Never disable dCEF on a Cisco 12000 series.

Disabling CEF on an Individual Interface

When you enable or disable CEF or dCEF in Global Configuration mode, all supported interfaces that support CEF or dCEF are affected. Some features on interfaces do not support CEF, such as policy routing. In that case, you will need to disable CEF on that interface.

To disable CEF on an interface, use the following command:

no ip route−cache cef

Configuring CEF Load Balancing

To enable per−packet load balancing, use the following command:

ip load−sharing per−packet

Disabling CEF Load Balancing

To disable per−packet sharing, use the following command:

no ip load−sharing per−packet

Enabling Network Accounting for CEF

To enable network accounting for CEF on the 8500 GSR to collect the numbers of packets and bytes forwarded to a destination, use the following command:

ip cef accounting per−prefix

Setting Network Accounting for CEF to Collect Packet Numbers

To set network accounting for CEF to collect the numbers of packets express−forwarded through a destination, use this command:

ip cef accounting non−recursive

Viewing Network Accounting for CEF Statistics

The information collected by network accounting for CEF is collected at the route processor. Distributed CEF information is collected by the line cards, not the route processor.

To view the statistics collected, use the following command:

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show ip cef

Viewing CEF Packet−Dropped Statistics

To view the number of packets dropped from each line card, use the following command:

show cef drop

Viewing Non−CEF Path Packets

To view what packets went to a path other than CEF, use the following command:

show cef not−cef−switched

Disabling Per−Destination Load Sharing

If you want to use per−packet load balancing, you need to disable per−destination load balancing. To disable per−destination load balancing, use this command:

no ip load−sharing per−destination

Viewing the Adjacency Table on the 8500 GSR

The following command allows you to display the adjacency table on the Cisco 8500 GSR:

show adjacency

The following command will allow you to get a more detailed look at the Layer 2 information adjacencies learned by the CEF ASIC:

show adjacency detail

Clearing the Adjacency Table on the 8500 GSR

To clear the adjacency table on a Cisco 8500 GSR, use the following command:

clear adjacency

Enabling Console Session Logging on a Set/Clear Command−Based IOS

Different variations of the set logging command affect session logging differently. To enable session logging for a console session, use the following command:

set logging console enable

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Enabling Telnet Session Logging on a Set/Clear Command−Based IOS

To enable session logging for a Telnet session, use the following command:

set logging session enable

Disabling Console Session Logging on a Set/Clear Command−Based IOS

To disable session logging for a console session, use the following command:

Catalyst5000> (enable) set logging console disable

System logging messages will not be sent to the console.

Catalyst5000> (enable)

Disabling Telnet Session Logging on a Set/Clear Command−Based IOS

To disable logging for the current Telnet session, use the following command:

Catalyst5000> (enable) set logging session disable

System logging messages will not be sent to the current login session. Catalyst5000> (enable)

Setting the System Message Severity Levels on a Set/Clear Command−Based IOS

The severity level for each logging facility can be set using the set logging level command. Use the default keyword to make the specified severity level the default for the specified facilities. If you do not use the default keyword, the specified severity level applies only to the current session. The command syntax is:

set logging level [all|facility] severity [default|value]

Here’s an example of the command’s use:

Catalyst5000> (enable) set logging level all 5

All system logging facilities for this session set to severity 5(notifications)

Catalyst5000> (enable)

Enabling the Logging Time Stamp on a Set/Clear Command−Based Switch

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