User Manual

Fabric OS 5.0.0 procedures user guide 109
The dynamic long-distance mode (LD) automatically configures the number of buffer credits required,
based on the actual link distance.
For the SAN Switch 2/8V, SAN Switch 2/16V, SAN Switch 2/32, Core Switch 2/64, and SAN
Director 2/128, the number of ports that can be configured per port group at various distances is
summarized in Table 16.
Table 16 SAN Switch 2/8V, 2/16V, 2/32, Core Switch 2/64, and SAN Director 2/128
For the SAN Switch 4/32, the number of ports that can be configured at various distances is summarized
in Table 17.
Table 17 SAN Switch 4/32
Configuring an extended ISL
Before configuring the ISL, ensure that the following conditions are met:
• Extended ISL support for HP StorageWorks 1 GB switches is limited as follows:
• Extended ISLs are not supported on HP StorageWorks 1 GB switches that are part of a fabric that
contains other HP StorageWorks switches.
• To support extended ISLs between HP StorageWorks 1 GB switches, the
fabric.ops.mode.longDistance parameter to 1 on all switches in the fabric. Each switch
must be disabled before setting this parameter. The SAN Switch 4/32 cannot be part of such a
fabric.
• For fabrics that contain a mix of HP StorageWorks switches, the
fabric.ops.mode.longDistance parameter must be set to 0 (the default). (Under certain
circumstances this mode needs to be enabled on switches running Fabric OS v3.x or v4.x. Talk to
your switch provider for details.)
• The ports on both ends of the ISL must have the same configuration.
• Use only qualified SFPs. Refer to your model’s hardware manual for details on SFPs.
Speed
(Gbps)
Number of Ports Allowed at Distance (km)
10 25 50 100 250 500
14 4 L1 mode: 4
LD mode: 3
up to 2 n/a n/a
24 3 n/a1n/an/a
4 n/a n/a n/a n/a n/a n/a
Speed
(Gbps)
Number of Ports Allowed at Distance (km)
10 25 50 100 250 500
1 32 32 32 up to 15 up to 6 up to 3
2 32 32 15 up to 7 up to 3 n.a.
4 32 15 7 up to 3 n.a. n.a.