HP StorageWorks 2/16 - SAN Switch, Manual

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ISL trunking user guide
152 Fabric OS 3.x Document Addendum
Add the following section at the end of Chapter 1:
Long-Distance Trunking
This section provides information on long-distance trunking between Fabric OS v3.2 switches,
including the SAN Switch 2/8 EL and SAN Switch 2/16. Long-distance ISL trunking is a new
feature for Fabric OS v3.2.x and Fabric OS v4.4.0.
Long-Distance Trunking Requirements
Requirements for ISL Trunking and Extended Fabrics in Fabric OS v3.2.x are as follows:
■
The ISL Trunking and Extended Fabrics licenses are required.
■
All trunk group ports must be part of the same quad.
■
All trunk group ports must be running at 2 Gbit/sec. ISL Trunking does not support 1
Gbit/sec speeds.
■
All trunk group ports must have similar deskew values.
■
ISL Trunking is automatically enabled between adjacent switches that support trunking.
■
All trunking ports in the same trunk group should be configured to be the same Extended
Fabrics distance (for example, LD - LD, L0.5 - L0.5, or L1 - L1).
■
As the distance increases, more buffer credits are needed, and fewer ports can form a trunk
group.
■
SAN Switch 2/8 EL and SAN Switch 2/16 ASICs limit buffer allocation to 63 maximum
per port, so long-distance trunks can be established only up to this buffer limit.
Long-Distance Trunking Summary
The following is a summary of SAN Switch 2/8 EL and SAN Switch 2/16 long-distance
settings and supported distances:
■
L0 less than or equal to 5 km and a 2-, 3-, or 4-port trunk group (normal distance trunking
allocates 26 buffer credits across 4 data VCs)
■
LE less than or equal to 10 km and a 2-, 3-, or 4-port trunk group (allocates 19 buffer
credits across VC2)
■
L0.5 less than or equal to 25 km and a 2- or 3-port trunk group (allocates 29 buffer credits
across VC2)
■
L1 less than or equal to 50 km and a 2-port trunk group (allocates 54 buffer credits across
VC2)
■
L2 less than or equal to 100 km (no trunking support)
■
LD less than or equal to 100 km (trunking supported at distances under 50 km)