Deployment Guide

500 Fabric OS Command Reference

53-1003131-01

iodSet

Enables in-order delivery (IOD).

SYNOPSIS iodset

iodset --help

DESCRIPTION Use this command to enforce in-order delivery of frames during a fabric topology change.

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 instance, a link goes

down), traffic is rerouted around the failure and some frames might be delivered out of order. This

command ensures that frames are not delivered out-of-order, even during fabric topology changes. It

enforces a sufficient delay between the event that causes an existing path to be removed and the

establishment of a new path, so that frames are delivered in order. However, this also means that frames

are dropped during the delay, causing I/O failures.

When used without operands, iodSet enables in-order-delivery of frames on a switch (legacy IOD

behavior). Frame loss is unavoidable when a port goes down.

IOD is disabled by default. Use iodShow to display current settings. Use iodReSet to restore the default

setting.

NOTES You can no longer use this command to manage Lossless DLS. Use dlsSet instead. The following

command options are deprecated in Fabric OS v6.4.0 and later:

• iodset --enable -lossLessDls

• iodset --disable -lossLessDls

• iodset --show

The execution of this command is subject to Virtual Fabric or Admin Domain restrictions that may be in

place. Refer to Chapter 1, "Using Fabric OS Commands" and Appendix A, "Command Availability" for

details.

OPERANDS This command has the following operands:

--help

Displays the command usage.

EXAMPLES To display the default legacy IOD setting:

switch:admin> iodshow

IOD is not set

To enable IOD:

switch:admin> iodset

IOD is set