[T11.3] Re: Point to Point login between two N-Ports (FCP-2 and FC-FS)

Steve Johnson sjohnson at ngs-hq.com
Mon Oct 14 02:25:30 PDT 2002

INCITS T11.3 Mail Reflector
The initiator should always send a PRLI regardless of the login results.
If the other device is capable of being a target it should receive a PRLI
If the other device is another initiator only it should receive an LS_RJT.
Some devices may have both target and initiator capabilities.


----- Original Message -----
From: "Kevin D Butt" <kdbutt at us.ibm.com>
To: <t10 at t10.org>; <t11_3 at mail.t11.org>
Sent: Friday, October 11, 2002 5:53 PM
Subject: [T11.3] Point to Point login between two N-Ports (FCP-2 and FC-FS)

> INCITS T11.3 Mail Reflector
> ********************************
> I have a question related to point-to-point login between two N-Ports
> the target N_Port_Name is higher than the initiator N_Port_Name.  The
> frames are sent, then the target sends the PLOGI frame because it has a
> higher N_Port_Name.  The initiator sends the LS_ACC frame.  The target
> waits for a PRLI from the initiator because the target is not allowed to
> send the PRLI.
> The initiator should send a PRLI if the other device is a target, but it
> does not know if the other device is a target yet.  If the initiator
> sends a PRLI and the other device is an initiator, then both initiators
> would be sending a PRLI.  If the initiator doesn't send a PRLI then no
> image pair can be established and no SCSI communication can occur between
> the two devices.
> The supporting text from FCP-2 and FC-FS are below.
> What is the correct behavior of the initiator?
> Is there a hole in FCP-2 or  FC-FS?
> If there is a hole in the standards, how can we work around the problem?
> (and the hole needs closed)
> FC-FS clause implies that there might be a scenario where
> N_Port_Names would not be exchanged in FLOGI.  Is is appropriate for the
> target to not send it's Port_Name in the FLOGI but then to send it in it's
> LS_ACC to the PLOGI?
> According to FCP-2 clause 6.2, "PRLI requests shall only be initiated by
> devices having the initiator capability. Devices having only target
> capability shall not perform a PRLI request."
> According to FC-FS clause, "If the N_Port_Names are exchanged
> during Fabric Login, the Nx_Port with the highest N_Port_Name shall
> transmit the PLOGI."
> According to FC-FS clause, "The Payload of FLOGI contains the
> Service Parameters of the Nx_Port, a 64-bit N_Port_Name of the Nx_Port,
> a 64-bit Node_Name."
> Thanks,
> Kevin D. Butt
> Fibre Channel & SCSI Architect
> IBM Tape Microcode,
> 6TYA, 9000 S. Rita Rd., Tucson, AZ  85744
> Tie-line 321; Office: 520-799-5280, Lab: 799-2869, Fax: 799-4138, Email:
> kdbutt at us.ibm.com
> To Unsubscribe:
> mailto:t11_3-request at mail.t11.org?subject=unsubscribe

To Unsubscribe:
mailto:t11_3-request at mail.t11.org?subject=unsubscribe

More information about the T10 mailing list