ATTO Technology Diamond Storage Array VT-Class - Manual (Page 28)

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ATTO Technology Inc. Diamond Storage Array Installation and Operation Manual
4.1 In-band CLI Over Fibre Channel
In-band Command Line Interface (CLI) configures and manages the Diamond-VT using SCSI-based
CLI commands over a Fibre Channel port connection.
In-band CLI allows a programmer to configure
the Diamond-VT while it is moving data. Using a
programmer’s interface, CLI commands as
described previously in this manual may be
implemented.
In-band CLI is implemented as part of LUN 0. It
uses a different LUN than the Diamond-VT, and
reports as a Storage Enclosure Services (SES)
device (device type 0x0D).
LUN 0 is visible on all Fibre ports but is actually
a single unit. The default value for LUN 0 is 0x00.
LUN 0 must be reserved for each Write
Buffer/Read Buffer pair, using the SCSI Reserve
command to insure integrity of the in-band CLI
session.
1 An initiator (host) sends a SCSI Reserve
command to LUN 0.
• If LUN 0 is not reserved by another initiator,
LUN 0 is now reserved and ready to begin a
new CLI session.
• If the Diamond-VT configuration is reserved
by a different CLI session (i.e. serial or
Telnet), the in-band session is not allowed to
modify the Diamond-VT configuration. If you
try, the results buffer of LUN 0 returns:
Process X has the configuration
reserved.
ID of this session = Y
Ready.
2 The initiator issues a SCSI Write Buffer
command to LUN 0. A Write Buffer command
must be accompanied by an ASCII buffer
representing the CLI command string such as
set DiamondName Omega1
LUN 0 executes the command line and create
feedback in the form of ASCII characters into a
buffer. This buffer is 8 KB and circular. Retrieve
the results by issuing a Read Buffer command
before issuing another Write Buffer command.
3 A subsequent Write Buffer command
executes the new command line and overwrites
the previous results in the buffer with new
results.
4 LUN 0 can be released by issuing a SCSI
Release command to the LUN after each
Write/Read Buffer pair, or multiple Write/Read
Buffer pairs.
I/O details
The buffer sent to the Services LUN during the
data out phase of a Write Buffer command must
be:
• ASCII data
• maximum 80 bytes length
• terminated with either a carriage return
character (0x0D), line feed character (0x0A) or
NULL character (0x00)
• Characters following the first carriage return
character, line feed character or NULL character
are ignored.
The buffer retrieved from the Services LUN
during the data-in phase of a
Read Buffer
command:
• ASCII data
• 8 KBytes (8192 bytes) in length
• terminated with a NULL character (0x00)
• Characters following the NULL character are
meaningless.
A CHECK_CONDITION,
INVALID_PARAMETER_IN_CDB is returned
Initiator (Host) Diamond-VT
Reserve LUN 0 return: “ok”
Write Buffer
LUN 0
bid ‘AA’
“get Temperature” executes the CLI
command, stores
output in buffer
Read Buffer
LUN 0
bid ‘AA’ return:”Temperature=28
C\r\n\Ready.\r\n\0”
Release LUN 0 return: “ok”