ATTO Technology VT-Class manual In-band CLI Over Fibre Channel, Details, Initiator Host Diamond-VT

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.

1An 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.

2The 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.

3A subsequent Write Buffer command executes the new command line and overwrites the previous results in the buffer with new results.

4LUN 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.

Initiator (Host)	Diamond-VT
Reserve LUN 0	return: “ok”
Write Buffer	executes the CLI
LUN 0	command, stores
bid ‘AA’	output in buffer
“get Temperature”
Read Buffer	return:”Temperature=28
LUN 0	C\r\n\Ready.\r\n\0”
bid ‘AA’
Release LUN 0	return: “ok”

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

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ATTO Technology Inc. Diamond Storage Array Installation and Operation Manual