FW 07.00.00/HAFM SW 08.06.00 McDATA Enterprise Operating System Command Line Interface User Manual (620-000134-720, April 2005)

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Enterprise Operating System Command Line Interface User Manual
perf
perf.preferredPath
The perf.preferredPath commands enable you to use the Preferred
Path feature to influence the route of data traffic that traverses
multiple switches or directors in a fabric. If more than one ISL
connects switches in your SAN, this feature is useful for specifying an
ISL preference for a particular flow.
The Preferred Path feature allows the user to enhance the system’s
path selection algorithm by providing the ability to prioritize ISLs for
a selected port on the switch. The Preferred Path capability
customizes the static load-balancing function by allowing the user to
specify an ISL preference for each remote domain. Preferred Path,
however, is still subject to the standard Fabric Shortest Path First
(FSPF) requirements, which allow the firmware to override the
configuration setting if errors are encountered.
The data path consists of the source port of the switch or director
being configured, the exit port of that switch or director, and the
domain ID of the destination switch or director. Each switch or
director must be configured for its part of the desired path in order to
achieve optimal performance. You may need to configure Preferred
Paths for all switches or directors along the desired path for a proper
multi-hop Preferred Path. (For examples of Preferred Path
implementation and other related information, see your product’s
Element Manager manual.)
The following rules apply when configuring Preferred Paths:
• The switch’s domain ID must be set to insistent.
• Domain IDs must be in the range of 1 through 31.
• The specified numbers for source ports and exit ports must be in
the range equal to the number of ports for the switch being
configured.
• For any source port, only one path may be defined to each
destination domain ID.
perf.preferredPath.clearPath
Syntax clearPath destDomainID sourcePort
Purpose This command deletes a preferred path. The command causes the
specified path to use a path selection algorithm that is different from