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1-132 EMC Connectrix DS-32B2 and ED-12000B Fabric OS Reference Manual
Telnet Commands
dlsSet Turn on dynamic load sharing option.
Syntax dlsSet
Availability Admin
Description Use this command to enable dynamic load sharing when a fabric
change occurs.
Routing is done on a per-source-port basis. 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 utilization, when there are multiple equivalent
paths to a remote switch, traffic is shared among all the paths. Load
sharing takes place when a switch reboots. In addition, if dynamic
load sharing is enabled, the optimal load sharing is recomputed
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 Nx_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 (refer to 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 being
delivered out of order. No frame loss occurs if IOD is off, but there is
still a short period of time when traffic is not forwarded. This period
of time is significantly shorter than when IOD is on, and is usually
less than 1 second.
Operands None