Administrator Guide

Merging Two Operational Stacks
The recommended procedure for merging two operational stacks is as follows:
1. Always power o all units in one stack before connecting to another stack.
2. Add the units as a group by unplugging one stacking cable in the operational stack and physically connecting all unpowered
units.
3. Completely cable the stacking connections, making sure the redundant link is also in place.
Two operational stacks can also be merged by reconnecting stack cables without powering down units in either stack. Connecting a
powered-up standalone unit to an existing stack leads to same behavior as when merging two operational stacks. In such cases,
Manager re-election is done and the Manager with the higher MAC address wins the election. The losing stack manager resets itself
and all its member units. After the reset, all the losing stack members join the winning stack to form a single stack. The winning stack
remains functional through the merge process. If the stack merge is performed in this way, then it is strongly recommended that the
user set the admin management preference of the desired winner stack manager to a higher value than the stack manager that
should lose the election.
NOTE: In case of a stack, when one unit member resets and joins the stack, momentary drops will be observed, which is
recovered after few seconds.
Verifying a Stack Conguration
The following lists the status of a stacked switch according to the color of the System Status light emitting diodes (LEDs) on its
front panel.
• Blue indicates the switch is operating as the stack master or as a standalone unit.
• O indicates the switch is a member or standby unit.
• Amber indicates the switch is booting or a failure condition has occurred.
Using Show Commands
To display information on the stack conguration, use the show commands on the master switch.
• Displays stacking roles (master, standby, and member units) and the stack MAC address.
show system [brief]
• Displays the FlexIO modules currently installed in expansion slots 0 and 1 on a switch and the expected module logically
provisioned for the slot.
show inventory optional-module
• Displays the stack groups allocated on a stacked switch. The range is from 0 to 5.
show system stack-unit unit-number stack-group configured
• Displays the port numbers that correspond to the stack groups on a switch. The valid stack-unit numbers are from 0 to 5.
show system stack-unit unit-number stack-group
• Displays the type of stack topology (ring or daisy chain) with a list of all stacked ports, port status, link speed, and peer stack-
unit connection.
show system stack-ports [status | topology]
Example of the show system brief Command
Dell# show system brief
StStack MAC : 00:1e:c9:f1:00:9b
-- Stack Info --
Unit UnitType Status ReqTyp CurTyp Version Ports
------------------------------------------------------------------------------------
0 Management online I/O-Aggregator I/O-Aggregator 8-3-17-46 56
1 Standby online I/O-Aggregator I/O-Aggregator 8-3-17-46 56
2 Member not present
3 Member not present
194
Stacking