Mstp Configuration Example - One Region; Figure 5: Mstp Example With One Region - Avaya 8600 Engineering

3. MSTP Configuration Example – One Region
For this configuration example, we will configure the following:

All switches are configured in the same region named region1 and using revision 1

C3750-1 will be configured so that it will become the CIST Root by configuring the lowest CIST
Priority of 4096.

C3750-2 will be configured so that it will become the CIST backup by configuring the next highest
CIST Priority of 8192.

Three VLANs will be configured, VLAN 200 for management and VLANs 1000 and 1100 for end
user access

For the management VLAN 200, we will configure a management IP address as shown in the
diagram above – for this example, no routes are configured for the management as it is a simple
Layer 2 network

We will configure two MSTI instances; MSTI 1 for VLAN 200 and 1000, and MSTI 2 for VLAN
1100 to load balance traffic as illustrated in the diagram above

C3750-1 will be configured as the root bridge for MSTI 1 and backup root for MSTI 2

C3750-2 will be configured as the root bridge for MSTI 2 and backup root for MSTI 1

8600-1 will be configured with a CIST and MSTI 1 priority of 12288 so that will become both CIST
and MSTI 1 root if both C3750-1 and C3750-2 should fail

8600-2 will be configured with a CIST priority of 16384 so that it will become CIST root if C3750-
1, C3750-2, and 8600-1 should fail
July 2010

Figure 5: MSTP Example with One Region

RSTP/MSTP Technical Configuration Guide
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