iSCSI Target support in OpenSolaris is undergoing change ...

In 2008.11, there is only one iSCSI Target
- It is the user-mode daemon process called 'iscsitgtd'
- It is enabled / disabled by SMF under the name svc:/system/iscsitgt:default
- It is administered by the CLI iscsitadm, or through the ZFS option of 
'shareiscsi'
- It encapsulates both the iSCSI protocol and SCSI Target Emulation in the same 
piece of software
- It listens for iSCSI Initiators on TCP/IP port 3260

In a future release of OpenSolaris, or by downloading the iSER packages from 
http://www.opensolaris.org/os/project/iser/, there is a new iSCSI Target
- It is a kernel-mode port provider that is part of the COMSTAR framework
- It is enabled / disabled by SMF under the name 
svc:/network/iscsi/target:default
- It is administered by the CLI itadm
- It encapsulates the iSCSI protocol in a port provider, leaving SCSI Target 
Emulation to the LUN provider in COMSTAR
- It listens for iSCSI Initiators on TCP/IP port 3260

As one can see from the software components above, the two iSCSI Targets 
implementations are completely different, with one notable exception, that 
being TCP/IP port 3260. Therein lies the problem reported in the base-note of 
this thread, in that two iSCSI Target implementation should not be listening 
and responding to iSCSI Initiator requests on the same TCP/IP port 3260.

Although this may seem like a glaring oversight, it is not. First, OpenSolaris 
2008.11 does not come with two iSCSI Targets, just one. Having two iSCSI 
Targets requires a system admin to download iSER support. By default both iSCSI 
Targets are disabled by default, which raises the question why would anyone 
want to run two?

Yes, that's a rhetorical question, as we all know this is OpenSolaris!

Yes, there are valid reasons for having both iSCSI Target implementations 
active at the same time, but for the same reason one can not have two web 
servers, two email servers, two whatever servers, running at the same time, 
their respective default TCP/IP port number needed to be changed.

So the solution is to change one or the other of the iSCSI Target 
implementations to listen on a TCP/IP port other then the default iSCSI Target 
port number of 3260.

For the iSCSI Target Deamon
# svccfg -s iscsitgt setprop iscsitgt/iscsi-port = integer: 3261
# svcadm restart iscsitgt

For the iSCSI Target Port provider
# itadm create-tpg [ tpg-name ] [IP-address[:port]] ...

For the (Solaris) iSCSI Initiator
# iscsiadm add discovery-address xxx.xxx.xxx.xxx:3261
{ Similar changes would be required for other non-Solaris iSCSI Initiators }

========================================

Notes about COMSTAR
- It is the kernel-mode framewaork
- It is enabled / disabled by SMF under the name svc:/system/stmf:default
- It is administered by the CLI stmfadm

Notes about the LUN provider in COMSTAR
- It is a kernel-mode LUN provider that is a part of the COMSTAR framework
- It is enabled / disabled as part of the COMSTAR framework
- It is administered by the CLI sbdadm
-- 
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