Apple has released today an article named "ACEs on Xsan volumes may appear as hexadecimal code"

This article addresses two common issues with Xsan :

• Local users appearing as hexadecimal codes on other clients
• How to delay the mounting of the Xsan volume

The second is very interesting. Sometimes, the Xsan volume mounts before the open directory master is available, resulting in incorrect ACE. A workaround would be to unmount and remount the volume. Here Apple provides a nice ruby script.

You can check this here : Xsan 2: ACEs on Xsan volumes may appear as hexadecimal code

Hope we'll have another script to delay the start of services such as iCal and AB.

Enlighten your Xsan with DiskFire.

We have been looking for a tool to test and tune the performance of Xsan volumes. We needed something that could generate concurrent IO to analyse the aggregate throughput of large SAN volumes. We also needed the ability to specify a path for the IO, so we could test individual Xsan affinities.

We couldn't find a nice tool to do this - so we decided to create our own!

Download it today - for free at www.factorial.co.nz/tools

DiskFire is specifically designed with Xsan in mind. Test your SAN perfomance by generating multiple concurrent IO streams. You can configure the size, blocksize, and the number of parallel IO threads. DiskFire lets you choose a target path for the IO, so you can test and tune down to individual affinities.

We are an independent IT consultancy focusing on the Apple platform. We offer a range of IT professional services including solution design, workflow optimisation and software development. We specialise in custom Final Cut Server integration, and Xsan / StorNext shared storage solutions.

This is just the first release of DiskFire and we would love the hear your feedback.

Cheers

Thomas Bauer + Tim Benson

Contact us at www.factorial.co.nz/contact

On Monday, Active Storage announced a couple of new options that a lot of us might be pretty interested in. The first is Active Stats, a monitoring and troubleshooting tool being debuted at NAB. For the press release on Active Stats:
http://www.getactivestorage.com/pr041210-2.php

The second is Innerpool, a card capable of hosting metadata storage for Xsan on SSDs embedded on the card. The card can then be installed in an Xserve. Using Innerpool you can free up those LUNs of Fibre Channel storage currently wasting away. Pretty interesting. For more see the press release at:
http://www.getactivestorage.com/pr041210-1.php

We had to deal with several emergency disaster recovery calls outside of our own customer support base last year and many of them were related to bandwidth expansion (Xsan 1.4.x — a lot of installations are still running on this, Xsan 2 and StorNext). We never recommend bandwidth expansion to our own customer base.

In the case of Xsan 2, even "successful" expansions (as indicated in the logs) were not successful. We saw cvfsck reporting bus errors after such "successful" expansions and in a few instances, we ended up recovering several terabytes of data as a last resort.

There is very little technical documentation at Apple or Quantum on issues like this, so we investigated this issue and simulated our own tests. I also had a lot of technical discussions with some of my peers and colleagues in Xsan, StorNext, QFS, GFS etc.

This article is a summary of the conclusions drawn from the above.

Those of you with large installations have probably considered Apple's Select, Preferred, or Alliance Support plans.

As of today, these plans include support for Xsan. This means a separate agreement for Xsan is no longer necessary.

It isn't too common to witness Apple forgoing a revenue opportunity. Optimistically, this is a sign of Xsan's maturity and ubiquity.

There's a forum discussion worth highlighting on tuning Xsan for small files. Thanks to user memblin for posting such a good summary of his experience.

We're hoping for a follow-up announcement real soon now...

Active Storage has released their long-awaited iPhone app. The app allows you to monitor (not change) the status of their line of RAID systems. Features include:

• Multiple systems can be monitored at once
• Various levels of detail, from at-a-glance summaries to controller utilization to individual drive status

Too bad you can't make the lights blink. The free app is available from the App Store, of course. Be the first to review it!

Quantum has released StorNext 4.0, highlighting the following new features:

• Replication; protecting business critical data off site, as well as furthering data distribution globally for improved workflows
• File System Deduplication; improving storage optimization, significantly reducing costs and management overhead
• High Availability (HA) enhancements; deliver the highest level of availability for increased uptime and business continuity
• Distributed Data Movers (DDM); eliminate I/O bottlenecks by acting as a conduit for passing data to and from storage tiers and archives
• Partial File Retrieval (PFR); streamline workflow in media asset management applications with timecode-based file retrieval

While Xsan shares much of its DNA with StorNext and can be used to make Macs into StorNext clients, many of the existing features in StorNext like the ability to manage tiered storage with Xsan metadata controllers or the Distributed LAN Client (which essentially delivers the SAN via ethernet alone) are absent from and unsupported for Xsan clients. However, the features that are particular to a StorNext metadata controller or Storage Manager environment can often be leveraged in StorNext environments that include Xsan clients. Apple tends to lag Quantum in issuing compatibility guidelines for Xsan and StorNext, so stay tuned and respect your version dependencies.

Apple has released Xsan 2.2.1, fixing several bugs in Xsan 2.2. The update is available through Software Update, or as separate installers for Mac OS X 10.6 and Mac OS X 10.5. An updated uninstaller is also available.

This update works only on existing installs of Xsan 2.2. As always, make sure your metadata controllers have OS and Xsan versions at least as great as all your clients. (This is sometimes difficult to control when updates arrive over Software Update. Be sure to manage your clients!) In addition, Apple warns that no Xsan settings should be changed during installation.

The update:

• Improves filesystem reliability
• Improves the cvfsck filesystem repair utility
• Resolves an issue that could cause QuickTime media to report "invalid public movie atom found" on playback
• Eliminates "An unknown disk has been inserted" message when mounting Xsan volumes (occurs in Mac OS X 10.5 Leopard only)