Technical data

Cisco SM-X Layer 2/3 EtherSwitch Service Module Configuration Guide for Cisco 4451-X ISR

Software Features

Cisco SM-X Layer 2/3 EtherSwitch Service Module Configuration Guide for Cisco 4451-X ISR

You can choose to gracefully power down your Cisco SM-X Layer 2/3 ESM before removing it from

router. This type of OIR is also known as managed OIR or soft OIR. The managed OIR feature allows

you to stop the power supply to your module using the hw-module subslot [stop] command and remove

the module from one of the subslots while other active modules remain installed on the router.

Note If you are not planning to immediately replace a module after performing OIR, ensure that you install a

blank filter plate in the subslot.

The stop option allows you to gracefully deactivate a module; the module is rebooted when the start

option of the command is executed. The reload option will stop or deactivate a specified module and

restart it. See the Shutting Down and Reloading the Cisco SM-X Layer 2/3 ESM for more information.

Preventing ESM from Automatic Reloads

The Cisco 4451-X ISR monitors the module status and recovers the module by reloading it when there

is a failure. After initiating a reload, router waits for 7 minutes for the module to be in an “OK” state. If

the module does not come to an “OK” state within these 7 minutes, the router considers this as a failure

and retries the recovery process. The maximum number of retry attempts that the router can make is 5.

After 5 such attempts, if the module does not come back to an “OK” state, the router puts the module in

an “Out of Service” state and terminates the error recovery process.

This behavior may create a problem in certain processes where booting a Cisco SM-X Layer 2/3 ESM

may take more than 7 minutes. For example, when booting the Cisco SM-X Layer 2/3 ESM with a new

IOS switch release, there can be microcode upgrade on the Cisco SM-X Layer 2/3 ESM by the new Cisco

IOS image. In such situations, prevent the router from automatically reloading the module after 7

minutes by disabling error recovery on a particular subslot. You can prevent the router from reloading

by enabling the maintenance mode. See the Enabling Maintenance Mode, page 6 for more information.

Once the module is placed into maintenance mode, you can bring it back into the normal operational

mode using the hw-module subslot x/0 reload command.

Enabling Maintenance Mode

We recommend that you enable the maintenance mode on the switch module when booting the module

with a new software image that requires bootloader upgrade and takes more than 7 minutes. Use the

hw-module subslot X/0 maintenance enable command to enable the maintenance mode. Enabling the

maintenance mode allows the switch module to take more than the default time limit of 7 minutes to

boot. When you fail to configure maintenance mode, the OIR timeout requests the module to go again

for reload. The switch module will be up and displayed as “out of service” in the show platform

command output on the host router but it remains operational. You can disable the maintenance mode

using the hw-module subslot X/0 maintenance disable command. Reload the module again to bring-up

the connection between the host router and the module.