Concept Guide
Example of the redundancy force-failover stack-unit Command
Dell#redundancy force-failover stack-unit
System configuration has been modified. Save? [yes/no]: yes
Proceed with Stack-unit hot failover [confirm yes/no]:yes
Dell#
Specifying an Auto-Failover Limit
When a non-recoverable fatal error is detected, an automatic failover occurs.
However, Dell EMC Networking OS is congured to auto-failover only three times within any 60 minute period and you cannot change that.
Disabling Auto-Reboot
To disable auto-reboot, use the following command.
• Prevent a failed stack unit from rebooting after a failover.
CONFIGURATION mode
redundancy disable-auto-reboot
Pre-Conguring a Stack Unit Slot
You may also pre-congure an empty stack unit slot with a logical stack unit.
To pre-congure an empty stack unit slot, use the following command.
• Pre-congure an empty stack unit slot with a logical stack unit.
CONFIGURATION mode
stack-unit unit_id provision S3048–ON
Example of Viewing a Logical Conguration of a Pre-Congured Stack Unit
After creating the logical stack unit, you can congure the interfaces on the stack unit as if it is present.
Removing a Provisioned Logical Stack Unit
To remove the line card conguration, use the following command.
• To remove a logical stack-unit conguration, use the following command:
CONFIGURATION mode
no stack-unit unit_id provision
Hitless Behavior
Hitless is a protocol-based system behavior that makes a stack unit failover on the local system transparent to remote systems. The system
synchronizes protocol information on the Management and Standby stack units such that, in the event of a stack unit failover, it is not
necessary to notify the remote systems of a local state change.
Hitless behavior is dened in the context of a stack unit failover only.
• Only failovers via the CLI are hitless. The system is not hitless in any other scenario.
Hitless protocols are compatible with other hitless and graceful restart protocols. For example, if hitless open shortest path rst (OSPF) is
congured over hitless the link aggregation control protocol (LACP) link aggregation groups (LAGs), both features work seamlessly to
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High Availability (HA)