HP StorageWorks Fabric OS 5.0.0 Features Overview (AA-RW1NA-TE, May 2005)

25Fabric OS 5.0 features overview
ISL Trunking
The ISL Trunking feature allows ISLs between two HP StorageWorks models to merge logically
into a group link. ISL Trunking reduces or eliminates situations that require static traffic routes
and individual ISL management to achieve optimal performance.
Trunking optimizes fabric performance by distributing traffic across the shared bandwidth of all
the ISLs in a trunking group. This distribution allows traffic to flow through any available link in
a group rather than restricting it to a specific, potentially, congested link.
Additional advantages
The following lists additional ISL Trunking advantages:
• Allows a simplified fabric design and management, lowered cost of ownership, and
increased data availability.
• Distributes traffic dynamically and in order at the frame level. This distribution scheme
allows the fabric to achieve greater performance with fewer ISLs.
• Is compatible with both short wavelength (SWL) and long wavelength (LWL) fiber optic
cables and transceivers.
• Is easily managed using either Fabric OS CLI commands or Advanced Web Tools. These
tools allow you to enable and disable trunking and set trunk port speeds for entire switches
or for individual ports.
Each switch that participates in trunking requires an ISL Trunking license. Trunking is enabled
automatically when the ISL Trunking license is activated and ports are reinitialized.
Improved throughput
Figure 2 illustrates how trunking can result in more throughput by distributing data over four
ISLs with no congestion. In a fabric that does not have trunking capability, some paths would
be congested and other paths underutilized.