Task Flow: Replace A Unit In The Stack - Avaya 4000 Series Troubleshooting Instructions

The Auto Unit Replacement (AUR) and DAUR features allow replacement of a failed unit in a
stack with a new unit, while retaining the configuration of the previous unit. The stack power
must be on during unit replacement.
After replacing the base unit, another unit in the stack becomes the designated temporary base
unit. The replacement base unit does not resume as the base unit automatically. The
replacement base unit must be configured as the base unit.
The replacement unit to the stack must be running the same software and firmware versions
as the previous unit but with a different MAC address.
Important:
If the stack is only of two switches, the remaining switch enters Stack Forced Mode if that
feature is enabled. Review the section
feature.
Important:
Different versions of the software and diagnostic images have different behaviors for the
software and diagnostic images. Review the section
(DAUR)

Task flow: Replace a unit in the stack

About this task
The following task flow assists you to replace one of the Avaya Ethernet Routing Switch 4000
Series devices in a stack. This is only appropriate if old software is used or AAUR is disabled.
If AAUR is available (and it is turned on by default in such cases), then the procedures to verify
software are not required.
Troubleshooting Avaya ERS 4000 Series
on page 42 regarding DAUR and its expected results.
Stack Forced Mode on page 29regarding this
Diagnostic Auto Unit Replacement
Replace a unit in the stack
April 2014 97