[Ovirt-devel] [Patch] Make iscsi targets for the developer versions

[mark wagner]

So from poking around a bit, with a single "tid" everything really gets rolled into one target 
(where target is node3:disk1)  Multiple tids allows for different targets. I've included tgtadm show 
data below for comparison.  I can code it either way. Just let me know which way we want it.

-mark

With a single tid:
[root at management ~]# tgtadm --lld iscsi --mode=target --op=show
Target 1: node3:disk1
     System information:
         Driver: iscsi
         Status: running
     I_T nexus information:
     LUN information:
         LUN: 0
             Type: controller
             SCSI ID: deadbeaf1:0
             SCSI SN: beaf10
             Size: 0
             Online: No
             Poweron/Reset: Yes
             Removable media: No
             Backing store: No backing store
         LUN: 1
             Type: disk
             SCSI ID: deadbeaf1:1
             SCSI SN: beaf11
             Size: 256M
             Online: Yes
             Poweron/Reset: Yes
             Removable media: No
             Backing store: /dev/VolGroup00/iSCSI3
         LUN: 2
             Type: disk
             SCSI ID: deadbeaf1:2
             SCSI SN: beaf12
             Size: 256M
             Online: Yes
             Poweron/Reset: Yes
             Removable media: No
             Backing store: /dev/VolGroup00/iSCSI4
         LUN: 3
             Type: disk
             SCSI ID: deadbeaf1:3
             SCSI SN: beaf13
             Size: 288M
             Online: Yes
             Poweron/Reset: Yes
             Removable media: No
             Backing store: /dev/VolGroup00/iSCSI5
     Account information:
     ACL information:
         ALL

With multiple tids we get this:

[root at management ~]# tgtadm --lld iscsi --mode=target --op=show
Target 1: node3:disk1
     System information:
         Driver: iscsi
         Status: running
     I_T nexus information:
     LUN information:
         LUN: 0
             Type: controller
             SCSI ID: deadbeaf1:0
             SCSI SN: beaf10
             Size: 0
             Online: No
             Poweron/Reset: Yes
             Removable media: No
             Backing store: No backing store
         LUN: 1
             Type: disk
             SCSI ID: deadbeaf1:1
             SCSI SN: beaf11
             Size: 256M
             Online: Yes
             Poweron/Reset: Yes
             Removable media: No
             Backing store: /dev/VolGroup00/iSCSI3
     Account information:
     ACL information:
         ALL
Target 2: node4:disk1
     System information:
         Driver: iscsi
         Status: running
     I_T nexus information:
     LUN information:
         LUN: 0
             Type: controller
             SCSI ID: deadbeaf2:0
             SCSI SN: beaf20
             Size: 0
             Online: No
             Poweron/Reset: Yes
             Removable media: No
             Backing store: No backing store
         LUN: 1
             Type: disk
             SCSI ID: deadbeaf2:1
             SCSI SN: beaf21
             Size: 256M
             Online: Yes
             Poweron/Reset: Yes
             Removable media: No
             Backing store: /dev/VolGroup00/iSCSI4
     Account information:
     ACL information:
         ALL
Target 3: node5:disk1
     System information:
         Driver: iscsi
         Status: running
     I_T nexus information:
     LUN information:
         LUN: 0
             Type: controller
             SCSI ID: deadbeaf3:0
             SCSI SN: beaf30
             Size: 0
             Online: No
             Poweron/Reset: Yes
             Removable media: No
             Backing store: No backing store
         LUN: 1
             Type: disk
             SCSI ID: deadbeaf3:1
             SCSI SN: beaf31
             Size: 288M
             Online: Yes
             Poweron/Reset: Yes
             Removable media: No
             Backing store: /dev/VolGroup00/iSCSI5
     Account information:
     ACL information:
         ALL
[root at management ~]#



Chris Lalancette wrote:
> Daniel P. Berrange wrote:
>>> My understanding of the iscsi target is admittedly weak, but I'm not sure this
>>> is what you want to do.  As I understand it, this will actually only create one
>>>  target (node5:disk1), with 3 LUN's, because you are overriding the tid in the
>>> top 3 lines.  I think what you probably want is one target per host, and then
>>> one LUN per target, so your commands would look something like:
>> Nah, you want the same target on all hosts so you can do migration and still
>> see the same storage. So one target, with 3 LUNS is a good setup IMHO.
> 
> Duh.  Excellent point.  Sounds like a good setup to me as well.
> 
> Chris Lalancette