Specifying Frame Order Delivery; Configuring The Link Cost For A Port - Brocade Communications Systems StoreFabric SN6500B Administrator's Manual

14

Specifying frame order delivery

You can enable this loss less feature from WT. If you try to enable loss less when DLS is OFF, an
error message displays.
To enable or disable loss less DLS, perform the following steps.
1. Open the Switch Administration window as described in
2. Select the Routing tab.
3. Select On in the Loss Less area to enable the mode, or select Off to disable dynamic load
4. Click Apply, and then click OK.
Specifying frame order delivery
In a stable fabric, frames are always delivered in order, even when the traffic between switches is
shared among multiple paths. However, when topology changes occur in the fabric (for example, if
a link goes down), traffic is rerouted around the failure, and some frames could be delivered out of
order.
By default, frame delivery is out-of-order across topology changes. However, if the fabric contains
destination devices that do not support out-of-order delivery, you can force in-order frame delivery
across topology changes.
Enabling in-order delivery (IOD) guarantees that frames are either delivered in order or dropped.
For more information regarding IOD, refer to the Fabric OS Administrator's Guide.
NOTE
Enabling in-order delivery can cause a delay in the establishment of a new path when a topology
change occurs, and therefore should be used with care.
To specify frame order delivery, perform the following steps.
1. Open the Switch Administration window as described in
2. Select the Routing tab.
3. Click On in the In Order Delivery (IOD) area to force in-order frame delivery across topology
4. Click Apply.

Configuring the link cost for a port

This section describes how to set the cost of an interswitch link (ISL). The cost of a link is a
dimensionless positive number. The fabric shortest path first (FSPF) protocol compares the cost of
various paths between a source switch and a destination switch by adding the costs of all the ISLs
along each path. FSPF defines the path with minimum cost. If multiple paths exist with the same
minimum cost, FSPF employs load sharing over these paths.
160
window" on page 31.
sharing.
When the exchange-based routing policy is in effect, the Loss Less DLS radio buttons display
on the Routing tab
window" on page 31.
changes or click Off to restore out-of-order frame delivery across topology changes.
"Opening the Switch Administration
"Opening the Switch Administration
Web Tools Administrator's Guide
53-1002756-01