Huawei S Series - 3 Small- and Mid-Sized Campus Networks

S Series Switches
iStack Technology White Paper
2 Technology Description
Issue 01 (2013-05-25)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
22
Figure 2-12 Original master and standby switches are in the same stack after the original stack
splits
SwitchA
Master
SwitchC
Slave
SwitchA
Master
SwitchB
Standby
SwitchC
Slave
SwitchD
Slave
Stack split
Stack1
SwitchB
Standby
SwitchD
Master
SwitchE
Slave
Stack2
SwitchE
Slave
Stack1
Figure 2-13 Packet exchange during a stack split
SwitchA
(Master)
SwitchB
(Standby)
SwitchC
(Slave)
Running state
Running state
Running state
SwitchD
(Slave)
SwitchE
(Slave)
Detects that the
master switch is lost
and then restarts
Detects that the
master switch is lost
and then restarts
Nbr Lost
Processes
the NBR Lost
packet in a
similar manner
as a member
switch leaves
a stack
A stack is set up