Re: iSCSI : Query about parameter exchange

[Bill Studenmund <wrstuden@wasabisystems.com>]

On Fri, 4 Oct 2002, Priya Viswambharan wrote:

> Hi all,
>
> I have a query about parameter negotiation/declaration.
>
> Consider the following scenario.
> I --> T    T=1, csg=0, nsg=3
>
> If the target has to send say its MaxRecvDataSegmentLength (or any other
> key which is not valid in the Security phase) to the initiator, is it ok
> for the target to respond with
> T --> I    T=0, csg=1
>             MaxRecvDataSegmentLength=<value>
> so that it can notify the Initiator of its capacity.

No. You can only exchange security parameters in Security phase.

Oh, you have to say csg=0 back since that was the stage the first packet
was in.

I think though that the target can say

T --> I T=1 csg=0 nsg=1

and then exchange keys in the normal phase.

> I believe there are some implementations that behave this way. In a
> Normal session, if such a login PDU is received from the Initiator the
> target can send its MaxRecvDataSegmentLength through a Text response in
> Full feature phase. But how could a target notify the Initiator of its
> MaxRecvDataSegmentLength in the following 2 scenarios : 1) a Discovery
> session 2) a Normal Session and the Initiator has not sent a text
> request to the target.

As above, the target just forces a normal negotiation phase, and all is
well.

Take care,

Bill