Cisco Configuring 1:1 Redundancy: Comprehensive Guide & Manual PDF

Information About 1:1 Redundancy

Configuring 1:1 Redundancy Enabling the 1:1 redundancy stack mode allows you to assign active and standby roles to specific switches in the stack. Prerequisites for 1:1 Redundancy, on page 1 Information About 1:1 Redundancy, on page 1 How to Configure 1:1 Redundancy, on page 2 Verifying the Stack Mode, on page 2 Configuration Examples for 1:1 Redundancy, on page 3 Additional References for 1:1 Redundancy, on page 3 Feature History for 1:1 Redundancy, on page 4 Prerequisites for 1:1 Redundancy The following are prerequisites for 1:1 redundancy: • All the switches in the stack must be running the same license level as the active switch.

For information about license levels, see the System Management Configuration Guide of the required release. • All the switches in the stack must be running compatible software versions. Information About 1:1 Redundancy 1:1 redundancy is used to assign active and standby roles to specific switches in the stack. This overrides the traditional N+1 role selection algorithm, where any switch in the stack can be active or standby. In 1:1 redundancy, the stack manager determines the active and standby role for a specific switch, based on the flash ROMMON variable. The algorithm assigns one switch as active, another switch as standby, designating all remaining switches in the stack as members.

When an active switch reboots it becomes standby and the existing standby switch becomes the new active. The existing member switches remain in the same state. Configuring 1:1 Redundancy 1

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Verifying the Stack Mode

How to Configure 1:1 Redundancy Enabling 1:1 Redundancy Stack Mode Follow these steps to enable the 1:1 redundancy stack mode, and set a switch as the active switch in a stack, or as the standby: Procedure Disabling 1:1 Redundancy Stack Mode On a switch where 1:1 redundancy is enabled, follow these steps to disable the feature. This changes the stack mode to N+1: Procedure Verifying the Stack Mode To verify the current stack mode on a switch, enter the show switch stack-mode command in priviledged EXEC mode. The output displays detailed status of the currently running stack mode. Configuring 1:1 Redundancy How to Configure 1:1 Redundancy Command or Action Purpose Step 1 enable Example:

Device> enable Enables privileged EXEC mode. Enter your password if prompted. Step 2 switch switch-number role{active|standby} Example: Device# switch 1 role active Changes stack mode to 1:1 mode and designates the switch as active or standby. Command or Action Purpose Step 1 enable Example: Device> enable Enables privileged EXEC mode. Enter your password if prompted. Step 2 switch clear stack-mode Example: Device# switch clear stack-mode Changes stack mode to the N+1 mode and removes active and standby assignments. Configuring 1:1 Redundancy 2

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Additional References for 1:1 Redundancy

Device# show switch stack-mode Switch Role Mac Address Version Mode Configured State --------------------------------------------------------------- 1 Member 3c5e.c357.c880 1+1' Active' Ready *2 Active 547c.69de.cd00 V05 1+1' Standby' Ready 3 Member 547c.6965.cf80 V05 1+1' Member' Ready The Mode field indicates the current stack mode The Configured field refers to the switch state expected after a reboot. Single quotation marks ( ' ) indicate that the stack mode has been changed. Configuration Examples for 1:1 Redundancy Example: Enabling 1:1 Redundancy Stack Mode You can use the switch switch-number role command to set the active and standby switch in 1:1 stack mode.

The stack operates in the 1:1 stack mode with the specified active or standby after reboot. In the following example, switch 1 is assigned the active role, and switch 2 is assigned the standby role. Device# switch 1 role active WARNING: Changing the switch role may result in redundancy mode being configured to 1+1 mode for this stack. If the configured Active or Standby switch numbers do not boot up, then the stack will not be able to boot. Do you want to continue?[y/n]? [yes]: yes Device# switch 2 role standby WARNING: Changing the switch role may result in redundancy mode being configured to 1+1 mode for this stack.

If the configured Active or Standby switch numbers do not boot up, then the stack will not be able to boot. Do you want to continue?[y/n]? [yes]: yes Example: Disabling 1:1 Redundancy You can use the switch clear stack-mode command to remove 1:1 stack mode, and change it back to N+1 stack mode. Device# switch clear stack-mode WARNING: Clearing the chassis HA configuration will resultin the chassis coming up in Stand Alone mode after reboot.The HA configuration will remain the same on other chassis. Do you wish to continue? [y/n]? [yes]:

Additional References for 1:1 Redundancy Related Documents Configuring 1:1 Redundancy Configuration Examples for 1:1 Redundancy Related Topic Document Title For complete syntax and usage information for the commands used in this chapter. See the Stacking and High Availability Commands section of the Command Reference for the release. Configuring 1:1 Redundancy 3

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Feature History for 1:1 Redundancy

Feature History for 1:1 Redundancy This table provides release and related information for features explained in this module. These features are available on all releases subsequent to the one they were introduced in, unless noted otherwise. Use Cisco Feature Navigator to find information about platform and software image support. To access Cisco Feature Navigator, go to https://cfnng.cisco.com . Configuring 1:1 Redundancy Feature History for 1:1 Redundancy Release Feature Feature Information Cisco IOS XE Everest 16.6.1 1:1 Redundancy Enables the 1:1 redundancy stack mode and enables you to assigns active and standby roles to specific switches in the stack. Configuring 1:1 Redundancy 4

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