Managing Device Information
Managing Stacking
Cisco Small Business SFE/SGE Managed Switches Administration Guide
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2
•
A stack is initially configured in chain topology and the units are connected
as follows:
Unit 2—Unit 5—Unit 1—Unit 4—Unit 6—Unit 8
The system administrator resets Unit 4 but does not realize that the Switch
Operation Mode After Reset field on the
System Information
page was
mistakenly checked as
stand-alone
. No physical connections are changed.
Unit 4 reboots in stand-alone mode, effectively cutting off Units 6 and 8
from the stack. Units 6 and 8 are shut down. The stack continues to operate,
but with Units 1, 2 and 5 being the only active units.
•
In the previous example, suppose that the system administrator realizes the
error after rebooting Unit 4 as a stand-alone device. The system
administrator should reboot Unit 4 in Stack mode. If the stack has not been
reset, the Master unit retains the original stack configuration file. Also, Unit 4
retains its stacking configuration information when its mode is changed
from Stack to stand-alone, and restores that information when returning to
Stack mode.
•
A stack is initially configured and all units are manually numbered. The units
are connected in a chain topology as follows:
Unit 2—Unit 5—Unit 1—Unit 3—Unit 4—Unit 6—Unit 7—Unit 8
Unit 3 fails. Since Units 4, 6, 7 and 8 are cut off from the Master unit, they are
automatically shut down. This leaves only Units 1, 2 and 5 running in the
stack.
The system administrator prepares a replacement unit by manually
renumbering a unit from another stack. However, the replacement unit is
mistakenly renumbered as Unit 4 instead of Unit 3. What happens if the
replacement unit is inserted into the running stack (in the same position as
Unit 3)? When the new Unit 4 is inserted into the running stack, the Master
unit executes Topology Discovery and discovers the new Unit 4. But now
the presence of the old Unit 4 is also discovered because of the revived
