Request: iSCSI Target Vendors - Solaris iSNS client support

Sun is working hard to implement iSNS client support for the Solaris iSCSI initiator in the near future. In preparation for this support our team has spent allot of time testing with different vendors hardware. Our development team has an interop lab containing hardware from most major iSCSI vendors. So this request is more for some of the smaller iSCSI vendors in the market space.

We have seen a couple issues with vendor implementations around iSNS. Those vendors have been notified and are working to resolve any issues with their devices. Again this request is really targeted to the vendors that we don't have hardware or time to test. For you we have a couple easy checks you can perform to verify your devices are going to work with the Solaris initiator's iSNS support.

Step 1.

Ensure your target can properly register with Microsoft's 3.0 iSNS server. (Yes, I said Microsoft. They have a good reference implementation of an iSNS server that is available for free, Today.)

Step 2.

When registering with the iSNS server make sure you are properly representing your portal groups. Specifically the PG Tag. This iSNS PG Tag should represent the same value received during an iSCSI full feature login for the TargetPortalGroupTag. If not our initiator will not trust the data you are returning and will fail the login.

We have seen two gotchas in this area with some vendor implementations

Gotcha 1.

If you don't register a PG Tag you are assigned a default PG Tag of 1 (RFC 4171 Section 6.5.4). In this case you must return a TargetPortalGroupTag of 1 during the iSCSI full feature login.

Gotcha 2.

Be careful in the ordering of your keys in your iSNS registration. If ordered wrong your PG Tag may be ignored by the iSNS server. As an example if you think you register PG Tag 5. I recommend you actually snoop/ethereal a trace of the value the iSNS server is returning to the initiator. It may have ignored the incorrect ordering of your keys and you also will gain the default PGTag of 1 causing the initiator to fail the login.

If you verify these two checks with you implementation you should be safe. In addition we hope to make our iSNS client support available via Solaris Express in the next couple months and recommend you test with our initiator.

Posted at 11:20AM Oct 14, 2005 by dweibel in General  |  Comments[0]