Dlsreset - HP StorageWorks MSA 2/8 - SAN Switch Reference Manual

Fabric OS Commands

dlsReset

Disable Dynamic Load Sharing (DLS) option.
Synopsis
dlsReset
Availability
Admin
Release
V3.1.x and V4.1.x
Description
Use this command to turn off Dynamic Load Sharing (DLS) when a fabric change
occurs. Refer to dlsset for a full description of load sharing.
Routing is generally based on the incoming port and the destination domain. This
means that all the traffic coming in from a port (either E_Port or Fx_Port) directed
to the same remote domain is routed through the same output E_Port.
To optimize fabric routing, when there are multiple equivalent paths to a remote
switch, traffic is shared among all the paths. Load sharing is recomputed when a
switch is booted up or every time a change in the fabric occurs. A change in the
fabric is defined as an E_Port going up or down, or an Fx_Port going up or down.
If DLS is turned off (using dlsReset), load sharing is performed only at boot
time or when an Fx_Port comes up. Optimal load sharing is rarely achieved with
DLS disabled.
If DLS is turned on (using dlsSet), routing changes can affect working ports.
For example, if an Fx_Port goes down, another Fx_Port may be rerouted from one
E_Port to a different E_Port. The switch minimizes the number of routing
changes, but some are necessary in order to achieve optimal load sharing.
These changes can further affect the performance of the fabric if the in-order
delivery (IOD) option is on. With the IOD option (see the iodSet command),
routes are not available for a few seconds after a fabric change. The time needed to
reset the fabric routing varies based on the size of the fabric. Some frame loss may
occur because as the fabric is recalculating routes, frames are dropped to avoid
216 Fabric OS Version 3.1.x/4.1.x Reference Guide