Справочник Пользователя для IBM Partner Pavilion T400
Speed
The Ultrium 2 Tape Drive’s Fibre Channel interface facilitates data at 2 Gb/s (200
MB/s). It automatically negotiates to a rate of 1 Gb/s (100 MB/s) if the system or
switch to which it connects does not support the 2-Gb rate (if this is the case, you
may experience performance degradation). You can force the drive to an explicit
speed by placing jumpers on the Fibre Channel (FC) configuration/status connector.
For more information, see “Step 4. Change the Link Services of the Drive (optional)”
MB/s). It automatically negotiates to a rate of 1 Gb/s (100 MB/s) if the system or
switch to which it connects does not support the 2-Gb rate (if this is the case, you
may experience performance degradation). You can force the drive to an explicit
speed by placing jumpers on the Fibre Channel (FC) configuration/status connector.
For more information, see “Step 4. Change the Link Services of the Drive (optional)”
Address Assignments
Each device on a Fibre Channel loop must have a Loop Identifier (LID) and a
corresponding Arbitrated Loop Physical Address (AL_PA) to communicate with other
devices in the topology. The AL_PA identifies the device on the loop. (LIDs and their
corresponding AL_PAs are listed in Table 5 on page 21 and Table 6 on page 22.)
You can set an AL_PA by using one of two methods known as soft addressing or
hard addressing.
corresponding Arbitrated Loop Physical Address (AL_PA) to communicate with other
devices in the topology. The AL_PA identifies the device on the loop. (LIDs and their
corresponding AL_PAs are listed in Table 5 on page 21 and Table 6 on page 22.)
You can set an AL_PA by using one of two methods known as soft addressing or
hard addressing.
Soft addressing allows the drive to dynamically arbitrate the AL_PA with other Fibre
Channel devices on the loop. Hard addressing allows you to choose the LID, which
determines the corresponding AL_PA. The higher the AL_PA, the lower the priority
of the device.
Channel devices on the loop. Hard addressing allows you to choose the LID, which
determines the corresponding AL_PA. The higher the AL_PA, the lower the priority
of the device.
Generally, servers (initiators) require that devices use hard addressing; they do not
support soft addressing. When setting addresses, assign the lowest AL_PA (and
thus the highest priority) to the server; assign the highest AL_PA (and thus the
lowest priority) to the drive.
support soft addressing. When setting addresses, assign the lowest AL_PA (and
thus the highest priority) to the server; assign the highest AL_PA (and thus the
lowest priority) to the drive.
To set soft or hard addressing, you must place jumpers on designated pins in the
drive’s LID/status connector (see (
drive’s LID/status connector (see (
2 in Figure 3 on page 15). The pin configuration
for soft and hard addressing is defined in “Setting the Arbitrated Loop Physical
Address (Fibre Channel Drive Only)” on page 19.
Address (Fibre Channel Drive Only)” on page 19.
Chapter 1. Introduction
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