Brocade Multi-Service IronWare Switching Configuration Guide (Supporting R05.6.00) - Manual (Page 629)

Multi-Service IronWare Switching Configuration Guide 599
53-1003036-02
About Multi-Chassis Trunk (MCT)
18
L2 protocol packet handling
The default behavior is to forward or flood STP and RSTP BPDU packets.
If the no cluster-l2protocol-forward command is configured on global basis or
cluster-l2protocol-forward disable is configured on a port, the STP protocol packets coming on the
MCT VLANs are dropped.
All other L2 protocol packets will be flooded on the MCT VLANs or dropped. The
cluster-l2protocol-forward command is not applicable to these protocol packets. It only applies to
STP or RSTP BPDU packets.
Forwarding broadcast, multicast and unknown unicast traffic
Traffic received from non-ICL ports is forwarded the same way as non-MCT devices.Traffic received
from an ICL port is not forwarded to the CCEP port if the peer MCT switch has the reachability to the
same cluster client.
Both the MCT nodes must be multicast enabled for multicast routing on MCT.
NOTE
When there is a double failure, the forwarding behavior will be unpredictable and there may be a
complete traffic loss. For example, when both the ICL cluster link and any one leg of the client CCEP
link fail. From the physical topology perspective, it may appear like a path is available, while traffic
may not be forwarded.
NetIron CES and NetIron CER forwarding
The ICL port must belong to VLANs that are cluster member VLANs.
Syncing interface MACs to peer MCT devices
The MCT device uses an interface MAC to identify the packets that are addressed to the switch.
Such packets may be received by a peer MCT device. The peer MCT device switches packets over
the ICL to the local MCT switch to be routed properly.
MCT L2 protocols
When configuring L2 protocols, you should consider the following.
MRP
• An ICL interface can not be configured as MRP secondary interface and vice-versa as the ICL
cannot be BLOCKING.
• MRP can not be enabled on MCT CCEP port and vice-versa.
G.8032
• If the port is an ERP interface, it can not be enabled as a CCEP port.
• If the interface is ICL interface it can not be configured with MS, FS or RPL.
• G.8032 and MCT are not supported together.