agspoon wrote:
> Thanks for the tip.  Yes, it really is LUN-0 that is missing.  All the
> other LUNs (1-6) do show up in this error condition, and upon reboot
> they all show up.  It is only an occasional boot up where I see LUN-0
> missing, and I wanted to avoid a reboot to restore it.  I'll give the
> re-scan trigger a try and see if LUN-0 shows up.
> What is the magic with the "- - -" that triggers the scan?  A bit of

It is :


"-" is a wild card.

For software iscsi the first two are going to be "-" or zero (iscsi 
always just uses 0), and then for LUN can you just use 0 if you are only 
looking for that one.

You can also run iscsiadm

iscsiadm -m session -r session_id --rescan
iscsiadm -m session --rescan

to scan all sessions.

> searching shows that many other people know about this, but I've
> somehow missed it. Is there any documentation that describes this
> interface (didn't see anything in the kernel docs)?
> Craig
> On Mar 25, 7:27 am, Konrad Rzeszutek <> wrote:
>> On Wed, Mar 25, 2009 at 08:26:46AM +0100, Ulrich Windl wrote:
>>> On 24 Mar 2009 at 19:47, agspoon wrote:
>>>> We have an occasional problem where one LUN of a target (LUN-0) does
>>>> not appear in a connection started by iscsistart.  This is in an iscsi-
>>>> root scenario where iscsistart is called from within the initrd
>>>> ramdisk image.  I don't why this happens, but I can detect when it
>>>> does.  However, I don't know how to stop the connection and try
>>>> again.  If I just re-run iscsistart, it complains that there is
>>>> already a connection.  I tried just pulling out all the iscsi related
>>>> modules and re-loading them, but they are "in use".
>>> Hi!
>>> I think that's not very iSCSI related, so my guess would be to keep the 
>>> connection
>>> and try a "rescan SCSI bus" on the SCSI host/connection that you already 
>>> have.
>>> Also, do you really need LUN 0? Disks are usually assigned to a LUN != 0.
>> They are with some iSCSI targets (MD3000i, DS3300, AX150, CX300, Compelant, 
>> DataCore,
>> and some other ones).
>> Do you have any other LUNs on the target except LUN-0? Do they show up?
>> If not, you can do 'echo "- - -" > /sys/class/scsi_host/hostX/scan" to
>> retrigger the scan. That should make the LUN-0 and others show up.
>> You will have to figure out the hostX relation to 
>> /sys/class/iscsi_session/sessionY
>> yourself.
> > 

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