Cisco Systems SG50028PK9NA Manual De Usuario

Master Selection Process

Cisco Small Business 200, 300 and 500 Series Managed Switch Administration Guide (Internal Version) 

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The following shows a case where one of the duplicate units is renumbered. The 
one with the lower MAC retains its unit ID (see 

 for a 

description of this process).

If a new stack has more than the maximum number of units (8), all extra units are shut 
down.

The master unit is selected from the master-enabled units (1 or 2). The factors in 
selecting the master unit are taken into account in the following priority:

•

Force Master—If Force Master is activated on a unit, it is selected. 

•

System Up Time—The master-enabled units exchange up-time, which is 
measured in segments of 10 minutes. The unit with the higher number of 
segments is selected. If both units have the same number of time segments, 
and the unit ID of one of the units was set manually while the other unit’s unit 
ID was set automatically, the unit with the manually-defined unit ID is 
selected; otherwise the unit with the lowest unit ID is selected. If both units 
IDs are the same, the unit with the lowest MAC address is chosen. Note: 
The up time of the backup unit is retained when it is selected as master in 
the switch failover process.

•

Unit ID—f both units have the same number of time segments, the unit with 
the lowest unit ID is selected.