Wednesday Oct 30, 2013

Back Up to Tape the Way You Shop For Groceries

Imagine if this was how you shopped for groceries:

  1. From the end of the aisle sprint to the point where you reach the ketchup.
  2. Pull a bottle from the shelf and yell at the top of your lungs, “Got it!”
  3. Sprint back to the end of the aisle.
  4. Start again and sprint down the same aisle to the mustard, pull a bottle from the shelf and again yell for the whole store to hear, “Got it!”
  5. Sprint back to the end of the aisle.
  6. Repeat this procedure for every item you need in the aisle.
  7. Proceed to the next aisle and follow the same steps for the list of items you need from that aisle.

Sounds ridiculous, doesn’t it?

Not only is it horribly inefficient, it’s exhausting and can lead to wear out failures on your grocery cart, or worse, yourself. This is essentially how NetApp and some other applications write NDMP backups to tape. In the analogy, the ketchup and mustard are the files to be written, yelling “Got it!” is the equivalent of a sync mark at the end of a file, and the sprint back to the end of an aisle is the process most commonly called a “backhitch” where the drive has to back up on a tape to start writing again.

Writing to tape in this way results in very slow tape drive performance and imposes unnecessary wear on the tape drive and the media, especially when writing small files. The good news is not all tape drives behave this way when writing small files. Unlike midrange LTO drives, Oracle’s StorageTek T10000D tape drive is designed to handle this scenario efficiently.

The difference between the two drive types is that the T10000D drive gives you the ability to write files in a NetApp NDMP backup environment the way you would normally shop for groceries. With grocery shopping, you essentially stream through aisles picking up items as you go, and then after checking out, yell, “Got it!”, though you might do that last step silently. With the T10000D, it has a feature called the Tape Application Accelerator, which prevents the drive from having to stop after each file is written to notify NetApp or another application that the write was successful.

When enabled in the T10000D tape drive, Tape Application Accelerator causes the tape drive to respond to tape mark and file sync commands differently than when disabled:

  • A tape mark received by the tape drive is treated as a buffered tape mark.
  • A file sync received by the tape drive is treated as a no op command.

Since buffered tape marks and no op commands do not cause the tape drive to empty the contents of its buffer to tape and backhitch, the data is written to tape in significantly less time. Oracle has emulated NetApp environments with a number of different file sizes and found the following when comparing the T10000D with the Tape Application Accelerator enabled versus LTO6 tape drives.

Notice how the T10000D is not only monumentally faster, but also remarkably consistent? In addition, the writing of the 50 GB of files is done without a single backhitch. The LTO6 drive, meanwhile, will perform as many as 3,800 backhitches! At the end of writing the entire set of files, the T10000D tape drive reports back to the application, in this case NetApp, that the write was successful via a tape mark.

So if the Tape Application Accelerator dramatically improves performance and reliability, why wouldn’t you always have it enabled? The reason is because tape drive buffers are meant to be just temporary data repositories so in the event of a power loss, there could be data loss in certain environments for the files that resided in the buffer. Fortunately, we do have best practices depending on your environment to avoid this from happening. I highly recommend reading Maximizing Tape Performance with StorageTek T10000 Tape Drives (pdf) to decide which best practice is right for you. The white paper also digs deeper into the benefits of the Tape Application Accelerator. The white paper is free, and after downloading it you can decide for yourself whether you want to yell “Got it!” out loud or just silently to yourself.

Customer Advisory Panel

One final link: Oracle has started up a Customer Advisory Panel program to collect feedback from customers on their current experiences with Oracle products, as well as desires for future product development. If you would like to participate in the program, go to this link at

photo taken on Idaho's Sacajewea Historic Biway by Rick Ramsey

- Brian Zents

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Tuesday Nov 22, 2011

Screwed Up Again, Did Ya?

Your turn to wear the Cantaloupe Cap of Shame? Here's how to keep it from happening again:

  1. Figure out what data you need to archive
  2. Create a solid archive someplace safer than your iphone
  3. Get wicked fast at recovering your system.

Jesse Butler explains how to do all three for a system running Oracle Solaris 11:

How to Recover an Oracle Solaris 11 System

- Rick


Thursday Mar 31, 2011

Magic Solution

Solution"Solution" is defined in the New Oxford American Dictionary as a means of solving a problem or dealing with a difficult situation. (Also, a liquid mixture in which the minor component (the solute) is uniformly distributed within the major component (the solvent)...) "Solution" as a term in our industry has been used and abused for as long as I remember. Everything is a solution if the problem is sufficiently atomic. I'm rather passionate about this because I have argued for years that a computer isn't a solution: solutions are built with computers, networks, software, procedures... everything it takes to resolve a problem. I'm on thin ice here, because I know there are those even more passionate, ready to pounce on any attempt at a definition, but I will define a solution as a comprehensive combination of components and procedures to solve a well-defined problem. The more non-trivial the problem, the more interesting the solution.

Since Oracle acquired Sun, we have been in a position to build complete, tested solutions to real problems. I know there are many who feel compelled to roll their own using what they consider to be best-of-breed components, but that shifts the burden of integrating, testing, and ongoing maintenance to a panoply of vendors. Do you want to get work done, or spend your resources grooming the tools that should be doing the work?

We have had a series of Oracle Optimized Solutions released over the last year. Most recently, we published Oracle Optimized Solution for Oracle Secure Backup. The problem? End-to-end archiving across a heterogeneous network in a manner that preserves system wide security, assures high availability, and that can scale to meet expanding needs. Simple? Not at all! The generic Oracle Secure Backup architecture supports multiple Media Servers working together under the administrative control of an Admin Server. Additional Media Servers can be deployed or multiple backup domains can be configured to address evolving scalability requirements. Using Oracle servers and the Oracle Secure Backup software, companies can implement cost-effective and powerful backup solutions for the largest, most diverse environments.

This comprehensive guide discusses the details: setup, sizing, and tuning best practices. At 41 pages, this is no marketing slideware and well worth the time to absorb.

- Kemer

Optimized Solution

Monday Feb 21, 2011

Red Tape, Part II


As I wrote last week, we recently announced the StorageTek T10000C Tape Drive, and along with it we released a number of related papers. I've been associated with publishing best practices papers for over a decade and it seems like there is no topic with less glamor for the writer – yet more importance for the reader – than the combined topics of backup/archive and restore/retrieve. The challenge has grown exponentially with the growth of disk storage. I remember the first time we sold a terabyte of storage: it was a room full of (big, heat-generating/power-consuming) 250 MB drives, costing millions of dollars. Now, just my home configuration consists of roughly 6 terabytes of disk.

How do you back up all of that storage? Tape: really fast tape. And, lots of it. This creates a whole variety of very interesting challenges today, elevating the topic to – at the very least – glamorous, but I think it qualifies as being downright hot! Fascinating areas include optimizing retrieving information from a vast achive of tape units, making sure that when you have backed up onto tape you can be sure it was done so without errors, and then there is the whole challenge of providing security. We have a paper for that!

Let's start off with the challenge of finding information on a serial, as opposed to random access, device. It can be done with brute force, and there are expensive solutions to assist, but the T10000C has a built in accelerator that relieves your system from the overhead. Learn how to use it by reading the concise Using Oracle's StorageTek Search Accelerator, by Oracle engineer Dwayne Edling.

Consider: you have invested big bucks to archive your priceless information onto potentially thousands of tapes. Of course, the latest tape drives all verify using ECC and CRC. However, these do not protect data that is being moved outside the storage device, resulting in a chance for data corruption as it is migrated across the storage landscape. The T10000C addresses this one step further by validating CRC check-sums generated at the host using Oracle's StorageTek Data Integrity Validation Solution (DIV). The brief article StorageTek Data Integrity Validation for the StorageTek T10000C Tape Drive, by the prolific Dwayne Edling, explains this problem in detail and presents some of the details of DIV.

Finally,we don't think twice about encrypting sensitive data on disks – what about on tape? One important aspect of enterprise security is the physical aspect: if someone stole the compact tape media, they could uncover all of your darkest secrets. The Oracle Key Manager (OKM) working with the Sun Crypto Accelerator 6000 provides a clean and highly efficient solution. You can read about this powerful combination in Oracle Key Manager Version 2.x Security and Authentication White Paper.

I have to be honest: I had never thought of Tape as a hot topic before. My bad!

- Kemer

Thursday Dec 30, 2010

Backing up the Toast

ZFS Storage Appliance

All hardware is vulnerable. You can live in a happy place, dreaming that disaster visits only others, but the day will come when it knocks on your door: usually at the most inopportune time. Think "quarter-end financial accounting!" This is why we back up everything we can. Or should...

Oracle's Sun ZFS Storage Appliances take care of many details for you, but they don't magically save your bacon: you have to work at it. Fortunately, they support the industry standard Network Data Management Protocol (NDMP) to ensure efficient data protection for backup and recovery. The Sun ZFS Storage appliance works with a variety of industry-leading backup applications (such as Oracle Secure Backup, Symantec NetBackup, and EMC Legato Networker) to offer a complete solution for data protection needs.

We have just published a paper that lays it all out for you: what NDMP is, how to configure your Sun ZFS Storage Appliance, and features and limitations in using Oracle Secure Backup, Symantec NetBackup, and EMC Legato Networker. So, before you burn the toast and start a kitchen fire with bacon, take a look at NDMP Implementation Guide for the Sun ZFS Storage Appliance!

- Kemer


Logan Rosenstein
and members of the OTN community


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