Understanding The Stack Topology; Stacking Failover Topology; Stacking Members And Unit Id - Dell PowerConnect 3524P User Manual

Understanding the Stack Topology

The PowerConnect 35xx series systems operates in a Ring topology. A stacked Ring topology is where all
devices in the stack are connected to each other forming a circle. Each device in the stack accepts data and
sends it to the device to which it is attached. The packet continues through the stack until it reaches its
destination. The system discovers the optimal path on which to send traffic.
Figure 1-3. Stacking Ring Topology
Ring Topology
Most difficulties incurred in Ring topologies occur when a device in the ring becomes non-functional,
or a link is severed. With the PowerConnect 3524/P and PowerConnect 3548/P stack, the system
automatically switches to a Stacking Failover topology without any system downtime. An SNMP message
is automatically generated, but no stack management action is required. However, the stacking link or
stacking member must be repaired to ensure the stacking integrity.
After the stacking issues are resolved, the device can be reconnected to the stack without interruption,
and the Ring topology is restored.

Stacking Failover Topology

If a failure occurs in the stacking topology, the stack reverts to Stacking Failover Topology. In the
Stacking Failover topology, devices operate in a chain formation. The Stack Master determines where the
packets are sent. Each unit is connected to two neighboring devices, except for the top and bottom units.

Stacking Members and Unit ID

Stacking Unit IDs are essential to the stacking configuration. The stacking operation is determined
during the boot process. The operation mode is determined by the Unit ID selected during the
initialization process. For example, if the user selected the stand-alone mode, the device boots in the
boot-up process as a stand-alone device.
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Introduction