Thanks Mike,

So what happens if we return the task set full or the busy status forever?
Does the host get an io error at a certain timeout, does the host silently
return back to the application that the operation has completed
successfully,  or does it retry indefinitely?

My concern is that the host is acknowledging the write to the application
after a timeout period for that pdu, which would explain the lost writes
during my target's rebuilds.


iscsi devel man.

On Thu, Aug 25, 2011 at 4:22 PM, Mike Christie <> wrote:

> On 08/25/2011 10:28 AM, iscsi developer man wrote:
> > Hey everyone,
> >
> > I am writing an iscsi target, and I am working on some experimental
> > features for dealing with rebuilds.
> >
> >
> > Right now, I am considering sending back to the initiator a
> > TASK_SET_FULL SCSI Status, and/or a BUSY SCSI Status, in the Command
> > Response PDU.
> >
> >
> > However, it looks like currently, it doesnt appear that its correctly
> What do you mean by it is not being handled? Are you returning task set
> fill and what is happening?
> > being handled. I.E. I am not acknowledging the writes, yet open-iscsi
> > thinks that they are being acknowledged.
> What do you mean by not acking writes? Do you mean with the task set
> fill status or do you mean you are also doing something like with the
> ExpCmdSn or some other value?
> >
> >
> > Is there a reason why this is?
> >
> > What is the initiator's expected behavior with regards to SCSI
> > Status's that are not SCSI_GOOD?
> The iscsi layer does not really do anything. It just copies the status
> and sense if needed to the scsi_cmnd struct and the scsi layer handles it.
> For BUSY status, the scsi layer will just retry the cmd immediately. For
> TASK_SET_FULL it will lower the devices queue depth and then retry
> immediately.

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