Owner's manual

Enclosure numb
er feature
This section provides a description of the purpose, function, and operation of the EMU enclosure number
(En) feature.
En description
In a single rack configuration, the En is a de cimal number in the range 00 through 14, which is
automatically assigned by the enclosure add ress bus.
NOTE:
Your storage system may use a n enclosure address bus higher than 14 if your c onfiguration includes an
optional expansion cabinet. The enclosure address bus connection determines the En. For a single rack,
the display is a decimal number in the range 01 through 14. For a multiple (two) rack configuration, the
display is decimal num ber in the range 01 through 24.
By default, the two-chara cter alphanumeric display shows this number. Pressing the bottom push button
changes the display to En,theEndisplaymode.
When the display is En, pressing and releasing the top push button displays the enclosure number.
A display of 00 indicates that the enclosure is not connected to the enclosure ad dress bus. When this
condition exists, there is no EMU-to-EMU communication over the enclosure address bus.
A display of 01 through 14 indicates that the enclosure is connected to the enclosure address bus and
can exchange information with other enclosures on the enclosure address bus. The decimal number
indicates the physical position of the enclosure in relation to the bottom of the rack.
• 01 is the address of the enclosure connected to the lower connector in the first (lower) enclosure
ID expansion cable.
• 14 is the ad dress of the enclosure closest to end of the bus, the upper connector in the last
(upper) ID expansion cable.
Unless there is an error c ondition, the display automatically returns to the enclosure number (01 through
14)oneminuteafterapushbuttonwaslastpressed.
Enclosure ad dress bus
The enclosure address bus provides a means for managing and reporting environmental conditions within
the rack. It is composed of enclosure I D expansion cables that interconnect the drive enclosures an d
controller enclosures. T wo drive enclosures connect to each enclosure ID expansion cable.
The drive enclosure numbers are always assigned by the enclosure address bus. Connecting the EMU
CAB connector to an enclosure address bus enclosure I D expansion cable automatically establishes an
enclosure number of 01 through 14. Any drive enclosure not connected to the enclosure address bus
has the enclosure number 00.
NOTE:
The enclosure number is automatically assigned. You cannot m anually assign an enclosure number.
The enclosures are numbered as shown in Figure 20.
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Enterprise Virtual Array hardware components