Broadcast Routing; In-Order Delivery; Reordering Network Frames - Cisco DS-C9216I-K9 Configuration Manual

Broadcast Routing

From the Fabric Manager, choose FC > Route Flow Statistics on the menu tree. The Information pane
Step 1
from Fabric Manager displays flows for multiple switches.
From the Device View, choose FC > Routes and click the Flow Statistics tab. The dialog box from the
Device Manager displays flows for a single switch.
Configure the flow attributes for the route.
Step 2
To add a route flow from Fabric Manager, click Create Row on the toolbar.
Step 3
To add a route flow from Device Manager, click Create in the dialog box.
You see the Create Route Flow dialog box.
Step 4 Complete the fields in this dialog box and click Create to add a route flow.
Broadcast Routing
Broadcast in a Fibre Channel fabric uses the concept of a distribution tree to reach all switches in the
fabric (for broadcast traffic).
FSPF provides the topology information to compute the distribution tree. Fibre Channel defines 256
multicast groups and one broadcast address for each VSAN. Switches in the Cisco MDS 9000 Family
only use broadcast routing. By default, they use the principal switch as the root node to derive the
distribution tree information. The protocols create a loop-free broadcast distribution tree.
Caution All switches in the fabric should run the same multicast and broadcast distribution tree algorithm to
ensure the same distribution tree.

In-Order Delivery

In-order delivery of data frames guarantees frame delivery to a destination in the same order that they
were sent by the originator.
Some Fibre Channel protocols or applications cannot handle out-of-order frame delivery. In these cases,
switches in the Cisco MDS 9000 Family preserve frame ordering in the frame flow. The source ID (SID),
destination ID (DID), and optionally the originator exchange ID (OX ID) identify the flow of the frame.
In case of a single switch, all frames received by a specific ingress port and destined to a certain egress
port are always delivered in the same order in which they were received.

Reordering Network Frames

When you experience a route change in the network, the new selected path may be faster or less
congested than the old route.
Cisco MDS 9000 Fabric Manager Switch Configuration Guide
21-8
Chapter 21 Configuring Fibre Channel Routing Services and Protocols
OL-7753-01