Intel IXM5414E - Blade Server Ethernet Switch Module SBCEGBESW User Manual page 283

This is a common network design. Through trunks, bridges C and D have redundant links to
backbone bridges A and B. Trunks, by default, carry all the VLAN traffic from VLAN 1 and VLAN
2. Therefore, bridge C is not only receiving traffic for VLAN 1, but also unnecessary broadcast and
multicast traffic for VLAN 2. Bridge C is also discarding one port for VLAN 2. Thus, there are three
redundant paths between bridges A and B, and two blocked ports per VLAN. This increases the
chance of a data loop.
273
Intel® Blade Server Ethernet Switch Module IXM5414E