Setting Port Speeds; Long-Distance Mode Definitions - HP A7533A - Brocade 4Gb SAN Switch Base Administrator's Manual

Setting port speeds

For long-distance ports, if a port is set to autonegotiate port speed, the maximum speed (which is 8 Gbps)
is assumed for reserving buffers for the port. If the port is only running at 2 Gbps this wastes buffers. For
long-distance ports, it is best to set the port speed (this applies to the 4/32 SAN Switch, 4/32B SAN
Switch and the 4/256 SAN Director only). On the HP StorageWorks 4/8 SAN Switch, 4/16 SAN Switch,
8/8 SAN Switch, 8/24 SAN Switch, SAN Switch 4/32, 4/256 SAN Director, 4/64 SAN Switch,
DC Director, 8/40 SAN Switch, and 8/80 SAN Switch platforms, for long-distance ports, you should
specify the port speed instead of setting it to autonegotiate.
IMPORTANT:
Director enterprise-class platform or between HP StorageWorks DC Director-to-DC Director enterprise-class
platforms with the appropriate blades, the 8/8 SAN Switch, 8/24 SAN Switch, 8/40 SAN Switch, and
8/80 SAN Switch, and the 8 Gbps supported SFPs installed.
The 8/8 SAN Switch, 8/24 SAN Switch, 8/40 SAN Switch, and 8/80 SAN Switch support long-distance
modes L0, LE, LS, and LD. The distance supported on each platform depends on the available buffers,
number of back-end ports, and number of offline ports.
Table 79

Long-distance mode definitions

Long-distance mode
L0
LE
LS
LD
You can set the port speed for one port or for an entire switch. Trunked ports must be set to the same
speed.
To set the speed for one port:
1. Connect to the switch and log in as admin.
2. Enter the portCfgSpeed command. The format is:
362 Administering ISL Trunking
Support for 8 Gbps is only between the HP StorageWorks 4/256 SAN Director to the DC
Distance
Normal
Up to 10Km
Static
Auto distance detect
Comments
Normal mode. More than one
data Virtual Channel is used. All
other modes use one data Virtual
Channel.
Reserves the buffers for 10 km
The distance statically specified
by you.
Reserves buffers for distance
specified in the CLI. Fabric OS
6.1.x supports up to 500 km at
1G up to 250 km at 2G, and
100 km at 4G and 8G.