Xsan Admin 1.2 has been released, and is available for download here. There are some very important instructions to follow on this upgrade – like, don’t upgrade from version 1.0 to version 1.2 directly. The full instructions for the update are available on Apple’s knowledge base. For more information about the upgrade, also refer to this article, and note the big red letters here about reading the instructions before upgrading. Of course, with any upgrade, we always recommend having an up-to-date back-up, and if you have the opportunity, to perform the upgrade on a test system before applying it to any production environment.
As with any upgrade, there are some substantial fixes in this, most notably, the invalid serial number issue has been resolved. As we mentioned in the 10.4.3 upgrade piece, there’s some improvement in AFP performance also. We are however still limited by the no greater than 2TB LUN support, this means that the new 7TB Xserve RAIDs still have to be sliced for use with Xsan to take advantage of all your new storage space.
The official list of improvements are available here.
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I can’t wait to see some performance reviews/numbers for AFP resharing!
In our test, we’ve seen around 70-80MB/s sustained from a server that was also the metadata contoller with about 10-12 clients all hitting it pretty hard, YMMV.
It’s important to remember that (1) metadata contollers should NOT be used to share out over AFP because (2) performance is linked to how quickly the metadata controller can respond to requests.