beautypg.com

General command support behavior, Multiple initiator support, Element addressing – Dell PowerVault ML6000 User Manual

Page 15: Command status

background image

PowerVault ML6000 SCSI Reference Guide

5

General Command Support Behavior

Multiple Initiator Support

Multiple initiators are not supported on the SCSI interface. Information such as unit attentions and sense
data will be held for only a single initiator. Multiple initiators are supported on the Fibre Channel interface.
Unit attentions and sense data will be held for each initiator.

Element Addressing

The element-addressing model follows that of previous Dell libraries. The starting addresses of the four
element types are:

0001h: Medium Transport

0010h: Import/Export

0100h: Data Transfer

1000h: Storage

Command Status

Individual command status responses are not documented, as they all follow the same general format as
described here. After processing any command, the library returns status from among the following:

Good - The library returns a Good status (00h) when it is able to process the command without errors.

Busy - The library returns Busy status (08h) when a motion command is still being processed, or the library
is generally not able to process additional commands at that time.

Reservation Conflict - The library returns a Reservation Conflict (18h) whenever an initiator attempts to
access a logical unit that has been reserved by another initiator, except for the following commands:

INQUIRY

LOG SENSE

MODE SENSE (Only PowerVault ML6000)

PREVENT/ALLOW MEDIUM REMOVAL

READ ELEMENT STATUS (only when the Current Data [CurData] field is set to 1)

REPORT LUNS

REQUEST SENSE

Check Condition - The library returns the Check Condition status (02h) when the following general
situations occur (all generate sense data):

The library is Not Ready (sense key 02h)

The library has encountered a Hardware Error (sense key 04h)

A parameter in the CDB is invalid or there is an invalid field in a parameter list, resulting in an Illegal
Request (sense key 05h)

A Unit Attention condition is pending (sense key 06h)

A command has been aborted (sense key 0Bh)