HP StorageWorks 1606 Brocade Fabric OS Administrator's Guide v6.3.0 (53-100133 - Page 108

Forcing in-order frame delivery across topology changes, Lossless Dynamic Load Sharing on ports

Page 108 highlights

4 Lossless Dynamic Load Sharing on ports By default, out-of-order frame-based delivery is allowed to minimize the number of frames dropped. Enabling in-order delivery (IOD) guarantees that frames are either delivered in order or dropped. You should only force in-order frame delivery across topology changes if the fabric contains destination devices that cannot tolerate occasional out-of-order frame delivery. Forcing in-order frame delivery across topology changes 1. Connect to the switch and log in as admin. 2. Enter the iodSet command. NOTE This command can cause a delay in the establishment of a new path when a topology change occurs; use it with care. 3. Confirm the in-order delivery has been set by entering the iodShow command. Restoring out-of-order frame delivery across topology changes 1. Connect to the switch and log in as admin. 2. Enter the iodReset command. Lossless Dynamic Load Sharing on ports Lossless Dynamic Load Sharing (DLS) allows you to rebalance port paths without causing input/output (I/O) failures in cases where the end devices require In-Order Delivery (IOD) of frames. You can use this feature with the Brocade 5100 and 5300 switches, and the Brocade DCX and DCX-4S enterprise-class platforms. You can use DLS on ports connecting switches to perform the following functions: • Eliminate dropped frames and I/O failures by rebalancing the paths going over the ISLs whenever there is a fabric event that might result in suboptimal utilization of the ISLs. • Eliminate the delay caused by establishing a new path when a topology change occurs. Configuring lossless dynamic load sharing on ports You configure load sharing on ports by using the iodSet command to specify that no frames are dropped while rebalancing or rerouting traffic. 1. Connect to the switch and log in using an account assigned to the admin role. 2. Enter the appropriate iodSet command to enable or disable dynamic load sharing. switch:admin>iodset --enable lossLessDLS switch:admin>iodset --disable lossLessDLS Lossless dynamic load sharing in Virtual Fabrics Enabling load sharing is optional on logical switches in a Virtual Fabric. If you enable this feature, it must be on a per logical switch basis and can affect other logical switches in the fabric. 66 Fabric OS Administrator's Guide 53-1001336-01

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66
Fabric OS Administrator’s Guide
53-1001336-01
Lossless Dynamic Load Sharing on ports
4
By default, out-of-order frame-based delivery is allowed to minimize the number of frames dropped.
Enabling in-order delivery (IOD) guarantees that frames are either delivered in order or dropped.
You should only force in-order frame delivery across topology changes if the fabric contains
destination devices that cannot tolerate occasional out-of-order frame delivery.
Forcing in-order frame delivery across topology changes
1.
Connect to the switch and log in as admin.
2.
Enter the
iodSet
command.
NOTE
This command can cause a delay in the establishment of a new path when a topology change
occurs; use it with care.
3.
Confirm the in-order delivery has been set by entering the
iodShow
command.
Restoring out-of-order frame delivery across topology changes
1.
Connect to the switch and log in as admin.
2.
Enter the
iodReset
command.
Lossless Dynamic Load Sharing on ports
Lossless Dynamic Load Sharing (DLS) allows you to rebalance port paths without causing
input/output (I/O) failures in cases where the end devices require In-Order Delivery (IOD) of frames.
You can use this feature with the Brocade 5100 and 5300 switches, and the Brocade DCX and
DCX-4S enterprise-class platforms.
You can use DLS on ports connecting switches to perform the following functions:
Eliminate dropped frames and I/O failures by rebalancing the paths going over the ISLs
whenever there is a fabric event that might result in suboptimal utilization of the ISLs.
Eliminate the delay caused by establishing a new path when a topology change occurs.
Configuring lossless dynamic load sharing on ports
You configure load sharing on ports by using the
iodSet
command to specify that no frames are
dropped while rebalancing or rerouting traffic.
1.
Connect to the switch and log in using an account assigned to the admin role.
2.
Enter the appropriate
iodSet
command to enable or disable dynamic load sharing.
switch:admin>
iodset --enable lossLessDLS
switch:admin>
iodset --disable lossLessDLS
Lossless dynamic load sharing in Virtual Fabrics
Enabling load sharing is optional on logical switches in a Virtual Fabric. If you enable this feature, it
must be on a per logical switch basis and can affect other logical switches in the fabric.