Dell PowerConnect B-FCXs Configuration Manual page 213

Figure 16
FIGURE 16
Active 1 (pri=30)
Standby 2 (pri=20)
Member 3 (pri=10)
Member 4 (pri=0)
Active 1 (pri=30)
Standby 2 (pri=20)
Member 3 (pri=10)
Member 4 (pri=0)
Active 1 (pri=100)
Standby 2 (pri=20)
Member 3 (pri=10)
Member 4 (pri=0)
Active 1 (pri=100)
PowerConnect B-Series FCX Configuration Guide
53-1002266-01
illustrates hitless stacking support during a stack merge.
Hitless stacking support during a stack merge
Stack 1
Active 1 (pri=100)
1
Standby 2 (pri=50)
Stack 1
Active 1 (pri=100)
Standby 2 (pri=50)
1
Member 3 (pri=0)
Member 4 (pri=0)
Stack 1/MAC A
Active 1 (pri=100)
Standby 2 (pri=50)
1
Member 3 (pri=0)
Member 4 (pri=0)
Device stack merge when the old Active controller comes back up
Active 2 (pri=50)
Standby 3 (pri=10)
Member 4 (pri=0)
Member 5 (pri=0)
PowerConnect B-Series FCX hitless stacking
Device stack merge
Stack 2
Member 1 (pri=30)
Member 2 (pri=20)
Member 3 (pri=10)
1
Member 4 (pri=0)
Active 5 (pri=100)
Standby 6 (pri=50)
When hitless failover is enabled, the stack with
more units will win. Stack 2 will reload and merge
with Stack 1. Stack 2 will retain its IDs.
Stack 2
Active 1 (pri=100)
Standby 2 (pri=50)
Member 3 (pri=0)
Member 4 (pri=0)
1
Member 5 (pri=30)
Member 6 (pri=20)
Member 7 (pri=10)
Member 8 (pri=0)
If the number of units in both stacks are the same,
the stack with the highest active priority will win.
Stack 1 will reload and merge with Stack 2.
Active 1 (pri=100)
Stack 2/MAC B
Member 2 (pri=20)
Member 3 (pri=10)
Member 4 (pri=0)
Standby 5 (pri=100)
1
Member 6 (pri=50)
Member 7 (pri=0)
Member 8 (pri=0)
If the number of units in both stacks is the same
and both Active controllers have the same priority,
the stack with the longer system up time (by 30
seconds or more) will win. Otherwise, the lowest MAC
address will win. Stack 2 will reload and merge with
Stack 1.
Active 1 (pri=100)
Standby 2 (pri=50)
Member 3 (pri=10)
1
Member 4 (pri=0)
Member 5 (pri=0)
Member 6 (pri=0)
When hitless failover is enabled, the stack with
more units will win. Active 1 will reboot and merge
with the stack.
5
1
1
1
1
1
1
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