Hi Paul,

 CML Does Target 0, then Lun0, the next volume will be target 0, LUN1,
etc.. With the standard two paths and two fault domains each server will
see four TARGETS, then the volumes will be LUNs underneath them.   As
opposed to EQL with Target 0, LUN 0 for first volume then Target 1 LUN 0
for next volume and so on.

 Gerry,

  Here are couple of links for working with Linux and Compellent Storage.

http://en.community.dell.com/techcenter/extras/m/white_papers/20421201/

http://en.community.dell.com/cfs-file/__key/telligent-evolution-components-attachments/13-4491-00-00-20-44-03-04/SC_2D00_Series_2D00_with_2D00_RHEL_2D00_7x_2D00_Dell_2D00_EMC_2D00_2018_2D002800_CML1071_2900_.pdf?forcedownload=true

http://en.community.dell.com/techcenter/extras/m/white_papers/20440304

If these don't help, please open a support case with Dell and they can
assist you. Debian isn't a supported OS, but RHEL and SuSE use same iSCSI
initiator.

Kind of sounds like a new UDEV rules needs to be created or modified.  But
that's a bit of a guess.

 Regards,

 Don



On Wed, Apr 11, 2018 at 2:21 PM, Paul Koning <paulkon...@comcast.net> wrote:

> Gerry,
>
> I'm not sure I understand the question.  iSCSI doesn't talk to LUNs, it
> talks to iSCSI targets.  You address targets (by their IP address).
>
> Once you're talking to a target, iSCSI provides a path for SCSI to do its
> thing with that target.  One of the things SCSI (not iSCSI) does is ask the
> target to "Report LUNs".  For most storage devices, a list of LUNs comes
> back, and SCSI will make each LUN it sees available as a Linux device.
>  (EqualLogic is an exception, it has just one LUN per target; but few
> targets, many more LUNs, is the much more common pattern and Compellent
> follows that common pattern.)
>
> The softlink you showed indicates that those LUNs are detected and mapped
> to /dev/sdX Linux block devices, as expected.
>
> One more point: Report LUNs will see the LUNs that the storage device
> wants you to see.  A lot of them do "LUN Masking" which means that only
> some LUNs are visible to a given client, according to access control
> settings.  If there are 20 LUNs, but LUN Masking is set so your client does
> not have permission to see 19 of them, then from your client only one LUN
> will appear in the Report LUNs reply, and only one /dev/sdX will be created.
>
>         paul
>
> > On Apr 11, 2018, at 7:24 AM, jmgerryobr...@gmail.com wrote:
> >
> > Hi,
> >
> >   How do you address more than one LUN in a target? We are trying to
> connect from Debian Stretch to an iSCSI volume in a DellEMC Compellent
> SC5050 array. In the Compellents the targets are the WQNs for the
> controller interfaces not the volumes Individual iSCSI volumes are given
> LUN numbers, eg. LUN1, LUN2, etc. Is there any way in open-iscsi to address
> individual LUNs within a given target? If we reboot the server the
> individual LUNs are connected to by the Device Mapper and given individual
> /dev/disk/by-path entries with "-lin-N" suffix (see below). We can't find
> any way to get open-iscsi to discover individual LUNs when there is more
> than on LUN attached to a target.
> >
> >     Can you help us please.
> >
> >         Regards,
> >            Gerry
> >
> > /dev/disk/by-path/ip-10.32.141.10:3260-iscsi-iqn.2002-03.com.compellent:5000d310055ba23d-lun-4
> -> ../../sdz
>
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