HP StorageWorks 2.32 Edge Switch - Manual (Page 158)

Optional features 158
• Domain RSCNs
This is a parameter in the Configure Switch Parameters dialog box, available from the
Configure menu in the Element Manager. Domain register for state change notifications
(domain RSCNs) are sent between end devices in a fabric to provide additional connection
information to HBAs and storage devices. As an example, this information might be that a
logical path has been broken because of a physical event, such as a fiber optic cable being
disconnected from a port.
If Enterprise Fabric Mode is enabled, this parameter is automatically enabled and cannot be
disabled unless the switch is offline. In this case, disabling Domain RSCNs also disables
Enterprise Fabric Mode.
• Insistent Domain Identification (ID)
This is a parameter in the Configure Switch Parameters dialog box, available from the
Configure menu in the Element Manager. Enabling this option sets the domain ID configured
in the Preferred Domain ID box in the Configure Switch Parameters dialog box as the
active domain identification when the fabric initializes. A static and unique domain
identification is required by the Fabric Binding feature because the feature's Fabric
Membership list identifies switches by WWN and Domain ID. If a duplicate preferred domain
ID is used, then insisted, warnings occur when directors and switches are added to a Fabric
Membership List.
If Fabric Binding or Enterprise Fabric Mode is enabled, this option is automatically enabled and
cannot be disabled unless these options are disabled or the switch is offline. Disabling insistent
domain ID will disable Enterprise Fabric Mode and Fabric Binding.
For More Information
See ” Enable/disable and Online State functions ” on page 152 for Fabric Binding and ” Enabling
or disabling switch binding ” on page 154 for Switch Binding.
To enable and disable this option, refer to the Enterprise Fabric Mode section of the HP
StorageWorks HA-Fabric Manager user guide.
Open Trunking
Interswitch links (ISLs) connect ports between E_Ports on Fibre Channel switches and link these
switches into a multiswitch fabric. Multiple ISLs may be connected between the switches in the
fabric. Data from an attached end device (server or storage) flows through these ISLs to a target
end-device connected to a switch somewhere in the fabric. A data flow is data received from a
specified receive port that is destined for a port in a specified target domain (switch). The list of ISLs
that are candidates for being rerouted (to or from) is derived from the fibre shortest path first (FSPF)
algorithm.
The Open Trunking feature monitors the average data rates of all traffic flows on ISLs (from a
receive port to a target domain), and periodically adjusts routing tables to reroute data flows from
congested links to lightly loaded links and to optimize bandwidth use. The objective of open
trunking is to make the most efficient possible use of redundant ISLs between neighboring switches,
even if these ISLs have different bandwidths.