I/o details, 1 in-band cli over the fibre channel – ATTO Technology Diamond Storage Array S-Class User Manual

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ATTO Technology Inc. Diamond Storage Array Installation and Operation Manual

5.1 In-band CLI Over the Fibre Channel

In-band Command Line Interface (CLI) configures and manages the Diamond Storage Array using
SCSI-based CLI commands over a Fibre Channel port connection.

In-band CLI allows a programmer to configure
the Diamond Storage Array 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 array, 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 array configuration is reserved by a

different CLI session (i.e. serial or Telnet),
the in-band session will not be allowed to
modify the array configuration. If you try, the
results buffer of LUN 0 will return

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

3

LUN 0 will execute 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.

4

A subsequent Write Buffer command will
execute the new command line and overwrite
the previous results in the buffer with new
results.

5

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 will be

• ASCII

data

• 8 KBytes (8192 bytes) in length

• terminated with a NULL character (0x00)

• Characters following the NULL character are

meaningless.

Initiator (Host)

Diamond Array

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=28C\r\n\Ready
.\r\n\0”

Release LUN 0

return: “ok”

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