Brocade Fabric OS Administrator's Guide Supporting Fabric OS v6.3.0 (53-1001336-02, November 2009)

Fabric OS Administrator’s Guide 487
53-1001336-02
FC Router port cost configuration
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You can connect multiple EX_Ports or VEX_Ports to the same edge fabric. The EX_Ports can all be
on the same FC router, or they can be on multiple routers. Multiple EX_Ports create multiple paths
for frame routing. Multiple paths can be used in two different, but compatible, ways:
• Failing over from one path to another.
• Using multiple paths in parallel to increase effective data transmission rates.
EX_Ports and VEX_Ports, when connected, are assigned different router port costs and traffic will
flow only through the EX_Ports. Routing failover is automatic, but it can result in frames arriving out
of order when frames take different routes. The FC router can force in-order delivery, although
frame delivery is delayed immediately after the path failover.
Source EX_Ports can balance loads across multiple destination EX_Ports attached to the same
edge fabric using exchange IDs from the routed frames as keys to distribute the traffic.
Setting router port cost for an EX_Port
The router port cost value for an EX_Port is set automatically when the EX_Port is created. However,
you can modify the cost for that port. You can configure the EX_ or VEX_Port with values of either
1000 or 10,000. If you want to differentiate between two EX_Port links with different speeds, you
can assign 1000 to one link and 10,000 to the other link.
For details about the use of any of the following commands, see the Fabric OS Command
Reference.
1. Enter the portDisable command to disable any port on which you want to set the router port
cost.
switch:admin> portdisable 7/10
2. Enable EX_Port or VEX_Port mode with the portCfgEXPort or portCfgVEXPort command.
switch:admin> portcfgexport 7/10 -a 1
3. Enter the fcrRouterPortCost command to display the router port cost for each EX_Port.
switch:admin> fcrrouterportcost
Port Cost
------------------------
7/3 1000
7/4 1000
7/9 1000
7/10 1000
7/13 1000
10/0 1000
You can also use the fcrRouteShow command to display the router port cost.
4. Enter the fcrRouterPortCost command with a port and slot number, to display the router port
cost for a single EX_Port.
switch:admin> fcrrouterportcost 7/10
Port Cost
------------------------
7/10 1000
5. Enter the appropriate form of the fcrRouterPortCost command based on the task you want to
perform:
• To set the router port cost for a single EX_Port, enter the command with a port and slot
number and a specific cost: