Dell PowerConnect PC7048R Technical White Paper - Page 21

Browse online or download pdf Technical White Paper for Switch Dell PowerConnect PC7048R. Dell PowerConnect PC7048R 34 pages. Stacking gigabit ethernet switches
Also for Dell PowerConnect PC7048R: Stacking Instructions (37 pages)

Dell PowerConnect PC7048R Technical White Paper
Stacking Dell PowerConnect 7000 Series Switches
If PoE is enabled on a switch port shortly before a master failover and the hardware status change had
not yet been communicated to the backup unit, the switch will continue to provide PoE power even
though PoE is not enabled for the port in the configuration on the new master. The user can correct
this configuration mismatch by re-enabling PoE on the port.

Stack Member Failover

When a unit in the stack fails, the master unit removes the failed unit from the stack. No changes or
configuration settings are applied to the other stack members; however, dynamic protocols will try to
re-converge as the topology could change because of the failed unit. When there are no connected
ports on the failed unit, the stack will be intact without any changes.

Failover Scenarios

This section describes examples of what happens when a stack member or the master unit fails.

Scenario 1

In this example, the stack has four members that are connected through a daisy-chain.
When all four units are up and running, the show switch CLI command gives the following output:
console#show switch
Managemen
Switch Status
------ ---------- ------------- --------- --------
1
Stack Mbr
2
Stack Mbr
3
Mgmt Sw
4
Stack Mbr
At this point, if Unit 2 is powered off or rebooted due to an unexpected failure, show switch gives
the following output:
Standby
Preconfig Plugged-in
Status
Model ID
Standby
PCT7048
PCT7048
PCT7048
PCT7048
Switch 1
Switch 2
Standby
Switch 3
Master
Switch 4
Model ID
PCT7048
PCT7048
PCT7048
PCT7048
Switch
Code
Status
Version
------------ --------
OK
4.0.0.6
OK
4.0.0.6
OK
4.0.0.6
OK
4.0.0.6
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