ATTO Technology V-Class Benutzerhandbuch

19

 

ATTO Technology Inc. Diamond Storage Array Installation and Operation Manual

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 available 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 does not allow 
modifications of the array 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 Buffe

r 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 overwrite 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.

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”