Gotta love the winter

In this time of great changes, I thought I might share a view from the ranch this morning.

Our cherry trees begin blooming after the rains start in November or December. They will continue to bloom for another month or two. For all of those people who are huddled against the cold, know that soon the changes will bring spring-like weather and the cherry blossoms will bloom.

Interesting new things shown at VMworld in Las Vegas

If you're traveling to Las Vegas for VMworld 2011, be sure to stop by the Nexenta booth. We've got some interesting new things to show... including something you've never seen before...

NexentaStor 3.1 Released

Today NexentaStor 3.1 was released to the world. Download a free trial copy today! We've been working hard on this release for some time and it offers significant improvements in stability and performance. Here is a small sample of the changes that I think are cool.

1. ZFS baseline
   zpool version 28 is the default pool version. This version includes a bunch of features that ZFS geeks know and love, such as readonly imports and rollback. Other Nexenta add-ons are also still there, such as WORM.
2. JBOD enumeration support
   One of the most difficult tasks of a general-purpose, x86-based storage appliance is sorting through the plethora of JBODs on the market and being able to reliably map a disk to the JBOD disk slot. This is the first release of this mapping capability in the appliance. Detailed support for a few JBODs is included (LSI DE1600, Xyratex HB 1234 and HB 2435), with generic support for other JBODs. The pipeline is full of JBODs waiting to have detailed support.
3. iSCSI performance improvements
   Several improvements in iSCSI performance, including zero-copy.
4. Vmware vStorage APIs for Array Integration support
   VAAI support has been added to block storage protocols.
5. Smarter fault triggers
   Many of the fault triggers have been improved to include more checks and better condition messages.
6. HA-Cluster feature enhancements
   Many enhancements to HA-Cluster to improve failover time and robustness. Also, you can now have multiple pools (Nexenta volumes) or virtual IP (VIP) addresses per cluster service. My favorite feature is that the requirement for a dedicated heartbeat disk has been removed, we now use shared pool disks for heartbeats, which makes perfect sense.
7. Auto-sync replication improvements
   The auto-sync asynchronous replication service has been redesigned to be more robust and offer better performance. A new one-to-many replication transport has also been added.
8. More devices supported
   Device drivers of note include: LSI 9205 family, Areca 1880. In the pipeline are driver updates from Intel and Emulex.
9. Better upgrade management
   You can now upgrade specific version numbers. In the past you would always be upgraded to the latest version, now you can specify the major version. For example, to upgrade to release 3.1, the NMC command is "setup appliance upgrade -r 3.1"
10. SMB improvements
    The SMB (aka CIFS) share service has improved performance, scalability, and reliability. 
11. Active Directory improvements
    AD integration has been significantly improved. AD also handles Domain Controller failover better. 
12. Virtual Machine Data Center improvements
    VMDC has better integration with VMware vmotion.

I tried to keep the list to the top-10, but that obviously didn't work. I hope you enjoy the release anyway!

NexentaStor 3.0.4 released

This week we've launched NexentaStor 3.0.4. In many ways this is a significant milestone, far beyond what may be immediately obvious. For existing Nexenta customers, the feature list will look largely unchanged -- many of the same, great universal storage features available since 3.0.0 earlier this year. But for one who studies how organizations grow and mature, the release represents the best quality, stability, and maturity ever. We have been working hard to earn your trust for protecting your data. I think you will be pleased with the result.

From a ZFS perspective, there have been many bug fixes and stability improvements. This release also deprecates the global ZIL disable feature. If you've ever attended my training courses or research sessions on ZFS, you know that I'm not a big fan of disabling the ZIL or the ease with which disabling the ZIL can be accomplished in NexentaStor. But there are a few, special cases where the performance trade-off is justified. In NexentaStor 3.0.4 you can set the ZIL use policy on a per-dataset basis. In ZFS terms, this is called "ZIL synchronicity" and is three parts really good stuff and one part pun. Special thanks to Robert Milkowski  and the ZFS community for the contribution.

In keeping with Nexenta tradition, a free, temporary licensed edition can be downloaded and installed from the main Nexenta site or the European mirror (thanks Jacco!) Give it a try and see why we think it is the best NexentaStor release yet. Of course, if you already have NexentaStor installed, the NMC command is "setup appliance upgrade" When you do the upgrade, a checkpoint will be made of your current system, so you can roll back if you are unhappy -- appliances are such wonderful things, when implemented properly.

Getting arrested at the World Cup celebration

Shortly after my arrival in Rotterdam last Sunday, the final game of the World Cup began. Though I am a soccer (and football) fan, I must confess that the trip was planned long before the Dutch secured a spot in the final. Arriving in the Netherlands after traveling for nearly 24 hours, I was looking forward to a quick nap before exploring the city. No rest for the weary. The party was already starting and people were collecting in a street near the Stadhuis, a mere block or two away from my hotel. Music was blaring from a rather impressive sound system and cold beer was flowing from the tap. How could I resist? Forget the nap, I'm going in!

The Sea of Orange (Zee van Oranje) was lively and exciting. I wandered through the streets and people seemed to be coming from every direction, flowing towards their favorite spot to watch the game. I grabbed a quick dinner from Dino's, a local restaurant, just before they closed to enjoy the festivities as the pregame broadcast started. Everyone seemed to be in high spirits, demonstrating their national pride.

That is when I got arrested.

The officer picked me right out of the crowd.

Clearly, I must have looked like a criminal?

I immediately wondered if they have racial profiling training, like the 'zonies.

The officer stopped me and asked a question, in Dutch, of course.

Whazzat?  I don't speak Dutch, or at least not in any way recognizable by someone who is actually fluent in Dutch.

Egads, I had only been in the country for a few hours and already I'm embroiled in an international incident.

Episodes from Locked up Abroad came flooding into my mind.

I had a vision of a tombstone engraved with "What was he thinking?"

Without missing a beat, the officer switched to English.

"I am from the Orange Police, and I see that you are not wearing Orange."

The horror!

The officer was quite right. I did not have anything Orange. My last Orange T-shirt was added to the rag pile just a few short months ago.

I knew was in big trouble -- time to act like a dumb American.

The setup: "I just arrived in the country..."

The excuse: "... and I have been trying to find a store to buy something Orange."

The saving grace: "Uh, and if you know of a store where I could find such things, I would promptly rehabilitate myself."

I managed a smile, in a hopeful attempt at leniency.

"Oh, well all of the stores are closed at 5 PM..."

Whoa! This might actually be working.

"... you will have to wait until later."

Reprieve?

"Meanwhile, get a beer and enjoy the game."

Free at last! Free at last! I had successfully negotiated my way out of jail in a foreign land, and the beer was very tasty, too!

The result of the game put a damper on the celebrations. Spain scored an impressive goal with just a few minutes before the end of overtime. The streets cleared and the city returned to normal. A national week of celebration was replaced with a warm homecoming for the National Team in Amsterdam. My newfound friends in Rotterdam were a pleasure and I am truly grateful for being a part of the festivities.

As for the Orange Police, I have learned my lesson and will never again transgress.

ZFS Training in Rotterdam next week

Next week I'll be offering an in-depth ZFS and NexentaStor training session in Rotterdam, the Netherlands. INPROVE is hosting the event and we have a full classroom. Though I did not plan for arriving in Amsterdam at the same time as the World Cup finals, I'm sure it will be a festive occasion. I'm sure my Spanish friends will understand that I will be wearing Orange.

Data protection beyond the pool

Many people are flocking towards ZFS solutions because of the sound, fundamental science behind ZFS and the features it provides. Two features which complete the hybrid storage pool design are separate logs and cache devices.

• Separate log devices allow you to direct synchronous write I/O destined for the ZFS Intent Log (ZIL), away from the main pool and towards devices which are optimized for low-latency writes. One of the best examples of a separate log device, highly optimized for low-latency writes, is the DDRdrive X1.
• Cache devices allow you to extend the RAM-based Adaptive Replacement Cache (ARC) by adding cache devices as a second-level cache (L2ARC). If the random read performance of the cache devices is much better than the rand read performance of the pool, then cache devices are more cost-effective than adding RAM to enlarge the ARC.

The data retention policies of the separate log and cache devices are quite different.

The cache device contains data that already exists on the pool devices. If a cache device fails, then a read access is treated as a cache miss and the data is retrieved from the pool. Sure, there might be a slight performance hit, but data is not compromised. Therefore, ZFS does not offer data protection (mirroring) for the cache devices.

Separate log devices contain data that is not yet written to the pool. If the separate log device fails while the pool is imported, then the device is taken offline and writes are sent to the pool. If the entire log device fails when the pool is exported, then ZFS will not allow the pool to be imported because it cannot determine if data has been lost. Hence, for separate log devices, ZFS offers mirroring to protect the data that has not yet been written to the pool.

Bottom line, if you are very concerned about the data retention of the pool and desire the cost-effective and high performance of the separate log and cache devices, then consider mirroring your separate log devices and don't worry about the cache devices.