Users Guide

Example
(Dynamic)
OS10# show mac address-table dynamic
VlanId Mac Address Type Interface
1 90:b1:1c:f4:a6:8f dynamic ethernet1/1/3
Example
(Ethernet)
OS10# show mac address-table interface ethernet 1/1/3
VlanId Mac Address Type Interface
1 66:38:3a:62:31:3a dynamic ethernet1/1/3
Supported
Releases
10.2.0E or later
Spanning-tree protocol
This section describes how spanning-tree features work and also about the different variants of STP.
Configuration notes
Dell EMC PowerSwitch S5200-ON Series and Z9332F-ON Series:
For RPVST with force-version STP convergence to work, ensure that the default VLAN is set to VLAN1. You must not configure
it to any VLAN number other than VLAN1.
Introduction to STP
The spanning-tree protocol is a Layer 2 network protocol that prevents loops in a network topology. Spanning-tree is useful
when more than one network path exists and devices in the network are either competing for or sharing these paths.
By eliminating loops, the protocol improves scalability in a large network and allows you to implement redundant paths, which
can be activated when the active paths fail.
Layer 2 loops occur in a network due to poor network design and without enabling xSTP protocols, can cause high switch CPU
utilization and memory consumption.
NOTE:
In L2 single rack, OS10 CLI is used to configure the spanning tree. For L3 fabric, SFS GUI is used to configure the
spanning tree.
Supported STP modes
The following variants of spanning-tree protocols are used in OS10 to provide a loop free layer 2 topology:
● Rapid Spanning Tree protocol can be seen as an evolution of the 802.1D standard. Primarily RSTP is created to address the
slow convergence nature of STP protocol (802.1D).
● Multiple Spanning Tree protocol (MSTP) defined in IEEE standard (802.1s), is an evolution of spanning tree protocols
allowing creation of multiple instance of spanning tree and mapping multiple VLANs to a specific spanning tree instance.
● Rapid per-VLAN spanning-tree protocol (Rapid-PVST) is a variant of RSTP protocol and supports creation of per VLAN
spanning tree instance to isolate link fluctuations only to a particular VLAN segment and also helps in load balancing across
different links.
● 802.1D STP Compatibility mode support. This mode enables the bridge to function as an IEEE Std 802.1D legacy STP
compatible mode while the system is running RSTP or MSTP modes of the spanning tree protocol.
● RSTP and MSTP are backward compatible with STP 802.1D. When an interface receives STP BPDU, the system responds
with the STP version of BPDU.
Change STP modes
The default xSTP variant running in OS10 is Rapid-PVST. You can change the mode to RSTP or MSTP using the spanning-
tree mode {rstp | mst | rapid-pvst} command.
Layer 2
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