Owner's Manual

538 | Chapter 18. STP
NETGEAR 8800 User Manual
• If the primary and backup nodes are not synchronized and both nodes are running a
version of XCM8800 that supports synchronization, proceed to
step 2.
• If the primary and backup nodes are synchronized, proceed to step 3.
2. If the primary and backup nodes are not synchronized, use the synchronize command to
replicate all saved images and configurations from the primary to the backup.
After you confirm the nodes are synchronized, proceed to step 3.
3. If the nodes are synchronized, use the run failover (formerly run msm-failover) command
to initiate failover.
For more detailed information about verifying the status of the primary and backup nodes,
and system redundancy, see
Understanding System Redundancy on page 64. For more
information about hitless failover, see Understanding Hitless Failover Support on page 69.
STP Configurations
When you assign VLANs to an STPD, pay careful attention to the STP configuration and its
effect on the forwarding of VLAN traffic.
This section describes three types of STP configurations:
• Basic STP
• Multiple STPDs on a single port (which uses EMISTP)
• A VLAN that spans multiple STPDs
Basic STP Configuration
This section describes a basic, 802.1D STP configuration. Figure 35 illustrates a network
that uses VLAN tagging for trunk connections. The following four VLANs have been defined:
• Sales is defined on switch A, switch B, and switch M.
• Personnel is defined on switch A, switch B, and switch M.
• Manufacturing is defined on switch Y, switch Z, and switch M.
• Engineering is defined on switch Y, switch Z, and switch M.
• Marketing is defined on all switches (switch A, switch B, switch Y, switch Z, and switch M).
Two STPDs are defined:
• STPD1 contains VLANs Sales and Personnel.
• STPD2 contains VLANs Manufacturing and Engineering.
The carrier and protected VLANs are also defined:
• Sales is the carrier VLAN on STPD1.
• Personnel is a protected VLAN on STPD1.
• Manufacturing is a protected VLAN on STPD2.