Dell Force10 C150 Configuration Manual page 968

Figure 46-13. VLAN Stacking without L2PT
Building A
You might need to transport control traffic transparently through the intermediate network to the other
region. Layer 2 Protocol Tunneling enables BPDUs to traverse the intermediate network by identifying
frames with the Bridge Group Address, rewriting the destination MAC to a user-configured non-reserved
address, and forwarding the frames. Since the frames now use a unique MAC address, BPDUs are treated
as normal data frames by the switches in the intermediate network core. On egress edge of the intermediate
network, the MAC address rewritten to the original MAC address and forwarded to the opposing network
region (Figure
FTOS Behavior: In FTOS versions prior to 8.2.1.0, the MAC address that Dell Force10 systems use to
overwrite the Bridge Group Address on ingress was non-configurable. The value of the L2PT MAC
address was the Force10-unique MAC address, 01-01-e8-00-00-00. As such, with these FTOS
versions, Dell Force10 systems are required at the egress edge of the intermediate network because
only FTOS could recognize the significance of the destination MAC address and rewrite it to the
original Bridge Group Address. In FTOS version 8.2.1.0 and later, the L2PT MAC address is
user-configurable, so you can specify an address that non-Dell Force10 systems can recognize and
rewrite the address at egress edge.
968 | Service Provider Bridging
no spanning-tree
BPDU w/ destination
MAC address: 01-80-C2-00-00-00
46-14).
Building B
X
no spanning-tree