HP C737990900 - Manual (Page 22)

22 Interface Implementation
The values of the names can be obtained using the Device Identification Vital
Product Information Page (part of the INQUIRY command).
Implications for Libraries
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Normally a standalone drive will operate using its own ‘hard’ names.
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The drive knows it is in a library or other ‘managed’ environment since one
of the signal lines on the ACI (Automation Control Interface) will be tied
down.
In this case, the drive will not go on the FC loop until it is told to. The library
can optionally download a new, soft base name (Port A/Device Name)
into the drive at this point. The drive will then use this as the origin of its
names. The library manufacturer would be responsible for obtaining this
IEEE Registered Name. It would be a property of the library, not the drive.
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If the library wants to ‘warm swap’ drives, it can. It just ‘turns off’ the drive
with the soft name using the ACI and then turns on the spare drive,
downloading the same name to it.
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If a drive is removed from the library, it will not have the ACI signal tied low
and so will revert to its original hard name. It should forget the soft name in
this case.
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If the library controller breaks, the drive will time out the ACI interface in
~10 seconds. The drive still knows it is in a library since the ACI signal is