RE: iSCSI: different question about terminated tasks

[Eddy Quicksall <eddy_quicksall@ivivity.com>]

Thanks, it was the abort that I really didn't understand.

It appears as though there is not "one ACA for each terminated task" ... do
you agree with that?

Eddy

-----Original Message-----
From: Elliott, Robert (Server Storage) [mailto:Elliott@hp.com]
Sent: Saturday, February 01, 2003 4:09 PM
To: ips@ece.cmu.edu
Subject: RE: iSCSI: different question about terminated tasks




> -----Original Message-----
> From: Eddy Quicksall [mailto:eddy_quicksall@ivivity.com] 
> Sent: Saturday, February 01, 2003 2:14 PM
> To: Mallikarjun C.; Bill Studenmund; ips@ece.cmu.edu
> Subject: RE: iSCSI: different question about terminated tasks
> 
> Here is how I understand ACA:
> 
> - one or more commands are in the enabled state
> - the commands are using NACA
> - one of the commands gets an error and reports a check condition
> - the ACA state is set
> - the rest of the commands are (1) aborted or (2) blocked 
> depending on mode page settings

The QERR and TST fields in the Control mode page offer more
combinations than that (for multiple initiators); see table 26 
in SAM-3 revision 4.

> - if aborted, the commands with the NACA bit set each give 
> ACA Active status; 

No; a command that has started processing does not get an ACA ACTIVE 
status.  It is either silently aborted or gets a TASK ABORTED status, 
depending on which initiator sent the task, which one sent the task 
which faulted, and the setting of the TAS bit in the Control mode page.

>                    the commands without the NACA bit give a 
> check condition that they were aborted???

No difference from commands with NACA set - they are silently
aborted or get TASK ABORTED status.

> - if a command without the ACA attribute is received while in 
> ACA, it gets ACA ACTIVE status

Yes.

> - commands with the ACA attribute enter the enabled state 
> (only one at a time allowed or it gets ACA Active)

Yes.

> - when finished with recovery, the initiator sends a Clear 
> ACA TMF to clear the ACA state

Yes.

> - if commands were blocked, they now go to the enabled state

Yes.

--
Rob Elliott, elliott@hp.com
Hewlett-Packard Industry Standard Server Storage Advanced Technology
https://ecardfile.com/id/RobElliott