How Healthy is Your Archive Data on Tape? HP StoreEver In Data Verification
for LTO-6
Like our health, early detection is the best way to avoid long-term problems with anything, including the precious archive data stored on your HP StoreEver LTO tape.
Much like your doctor, HP StoreEver Data Verification software performs a variety of check-ups on your tape data and returns health information. It allows for quick checkups or more in-depth analysis, so you can keep your data in good health. Let’s take a look at how this works and why it’s an important practice for long-term archive.
What is HP StoreEver Data Verification?
HP StoreEver Data Verification (HP DV) software is built
exclusively for HP StoreEver LTO tape drives for measuring the health of your
data stored on LTO tape. It allows the user to do a Quick, Moderate, or Full
test of the data cartridge as outlined here:
- Quick: Reads in both the forward and the
reverse direction in the regions of data around the edges where damage is
most likely to occur. This test takes approximately 5 minutes per tape for
verification.
- Moderate: Performs more in depth
verification than the Quick test and verifies up to 20% of the data
available in the tape.
- Full: Verifies all data in the tape. The
time it takes to perform a full test varies depending on tape type and how
much data is on the tape.
HP DV can also test the drive itself to ensure that the drive is not introducing errors during the verification process. The entire data verification test is run inside the drive so there is no impact on the host or the data path and data verification can be run in the background. It can be executed from the Command View TL console that can monitor the test progress and present the results.
Data verification can verify both offline tapes loaded into a dedicated library partition and tapes in other partitions in the same tape library without disrupting the application using those tapes. It also offers an API (Application Programmable Interface) for third party software integration, thereby making this process even easier and controllable from within the archiving application. The HP tape-as-NAS solution has HP Data Verification integrated into the solution with QStar Archive Manager.
How does HP StoreEver Data Verification work?
While LTO is an open standard, each vendor has implemented their own specific designs with unique capabilities and features. Understanding the inner workings of the tape drive and how data is read from the tape is key to accurately measuring the health of data on a given cartridge. It uses a combination of different routines and algorithms to read back data from the tape. Standard ISV applications typically only determine if your data is readable or not by using SCSI READ and/or VERIFY commands. These applications have no way of knowing just how hard the drive had to work to retrieve the data. HP Data Verification runs very specific read exercises on specific sections of the tape to maximize the effectiveness of the test. During the read operations, detailed information is collected from the various read algorithm engines. This information is analyzed using in-depth knowledge of the read mechanism in the drive and an assessment can be determined. A health indicator is returned as: Poor, Fair, Good or Great. This information can be used to determine if the data should be migrated to a new cartridge before the data becomes unreadable.
Why use HP StoreEver Data Verification?
As you can see, it’s important that we have measurable information about the health of our data on tape. Tapes can be mishandled or dropped and despite the excellent recovery mechanisms in the HP tape drives, damage to the tape may occur. We need to know if the data is suspect or even degrading over time. If we use simple tools that just read the data, we won’t know we have a problem until it’s too late and we potentially suffer a loss of data. HP StoreEver Data Verification gives you the tools and information you need for early detection. As an integrated part of the tape-as-NAS solution with QStar Archive Manager, keeping your data safe is simple and easy to use. If your data is important enough to archive, then performing regular health checks should be part of your data management routines.