Resource Library

FAQs

IBM (IBM i)

What is virtual tape?

A virtual tape system is a storage device that uses rotational disk to emulate physical tape drives and tape libraries. It is desirable to use disk as a storage media because it is much faster than traditional tape drives and also more dependable and flexible. Virtual tape systems look just like tape drives and tape libraries to the operating system; tapes can be mounted, scratched and used just like a real tape. Virtual tape systems come in many different form factors Dynamic Solutions International sells both self-contained appliances and head units that attach to external RAID disk systems and use either Fibre Channel or iSCSI to attach to servers or storage networks.

How does the DSI VTL compare to ProtecTier?

DSI and ProtecTier virtual tape libraries are similar. The DSI VTL had slightly better performance throughput numbers during qualification testing, offers the ability to create physical tape behind the VTL, and also has software integration with BRMS to provide a fully automated solution (Conductor is sold separately through DSI).

What type of tape libraries does the DSI VTL emulate?

The VTL can emulate 11 different manufactures and 59 different models of library. We typically configure the TS3500 library emulation for IBM i Hosts.

What type of tape drives are emulated?

This depends on the library being emulated, but for the TS3500 we offer the range of Ultrium1-7 (LTO1-7) and 3592 (03592J1A, TS1120, TS1130, TS1140) drive emulations. However, as a best practices we suggest emulating the IBM TS3500 tape library for use in IBM i environments.

How do I size a DSI VTL?

DSI & IBM use a proprietary sizing tool developed jointly to parse the output of BRMS text reports to generate an initial sizing. To gather the appropriate sizing for the VTL please refer to this link:

https://www.ibm.com/developerworks/community/wikis/home?lang=en#!/wiki/IBM%20Removable%20Media%20on%20IBM%20i/page/DSI%20VTL%20Sizing

However, it is strongly recommended that a solution be sized using the BRMS method rather than estimates to achieve the most accurate sizing & best performance. Please reach out to DSI for assistance with properly sizing a solution for your specific environment!

What types of hard drives are being used in the DSI VTL appliance?

The DSI-D24 appliance uses NL-SAS (SED) drives. The DSI EV0/EVD models use a pair of NL-SAS drives (RAID1) for the operating system but, will utilize Fibre Channel attached SAN storage for the data LUN’s.

Are there any plans on moving from the SHA-1 hashing algorithm for deduplication to eliminate the possibility of hash collisions?

Currently No, the likelihood of a hash collision is so improbable that it does not make sense to move to a different algorithm at this time. We absolutely have the capability to move toward a different mechanism that eliminates the possibility of hash collisions, but you are sacrificing performance by implementing that solution for prevention of a collision that is extremely unlikely to occur in the usable life of a VTL system.

Is deduplication configured at the server level, or is it possible to choose in-line or post-process option at the virtual library level (assuming there are several virtual libraries defined on the same server)?

Deduplication is policy driven on DSI VTL systems. Policies are defined through the VTL to which virtual tapes are then added. Multiple policies can be defined for use with different groups of tapes. Each individual policy specifies the type of dedupe (i.e. inline, turbo or post-process), replication, scheduling and dedupe priority to be used.

How does post-process deduplication work?

DSI VTLs can perform inline or post process deduplication. The post process deduplication allows the backup to be completed in the shortest amount of time by writing directly to disk (landing space) then being deduplicated at a later time. The data is read in by the head node and written to a temporary landing space, once the backup job completes, the deduplication engine reads the data from the temporary landing space, performs the deduplication functions, and stores the unique data blocks in the Single Instance Repository.

What is DSI VTL Conductor software? What are the benefits?

VTL Conductor is an application that runs on the IBM i to help automate Media Management to VTL functionality. Conductor can automatically configure the VTL to match what is currently in BRMS, so rather than manually creating libraries, drives and media counts, Conductor does that automatically for you. Also when you create new media class or migrate from another VTL conductor will automatically add those tapes to a defined deduplication policy. Otherwise you would have to do this manually through the VTL GUI console. Conductor also brings event logs and warning messages to the IBM i so that warnings are seen in the system operator queue and messages can be viewed in the event log.
Automatically identifying, importing, deduplicating and replicating unexpired legacy media from one or more legacy backup devices and automatically adjusting BRMS media data to reflect applicable changes (e.g. location, class, etc.).

Automatically securing live media in the virtual vault and returning media to its home library at expiration, or moving virtual media between libraries, each driven by media management system move instructions or BRMS/Tracker manual location changes to guide movement.

Creating automated, scheduled, policy-driven actions to manage virtual media duplication, consolidation and/or archival activities, all managed and executed from a single point.

What Fibre Channel cards are used?

DSI currently uses the Qlogic 2662 dual port 16GB HBA in our node and appliance solutions.

For the DSI-D24 model, does the 24TB capacity include RAID, metadata allocation, deduplication, etc?

The D24 is a preconfigured (meaning RAID6+1, cache, OS and logging space are accounted for) appliance that has a maximum capacity of 24TB of deduplicated data (This will be a 24TB space allocated for only the deduplication repository). So if you are taking a 5:1 dedupe ratio into account the D24 would allow you to backup ~120TB of raw data.

Are there any plans on a larger (than 24TB) appliance?

Yes, We announced our 48TB appliance Q3 of 2019. This 48TB appliance is now our largest appliance available. If backup requirements are larger than 48TB of deduplicated data the EV0/EVD node solution is the appropriate choice.

It seems that the (standalone) appliance is more attractive with inline dedupe, is this correct?

It depends: The (standalone) appliance can only scale up to 48TB of deduplicated repository storage, and cannot be expanded beyond that size because both the deduplication and VTL functions share the same resources in a single appliance (impacting both performance and scalability). For larger environments, node solutions can be configured in a cluster for global deduplication, providing a higher performance enterprise solution for customers that require backup and deduplicate of larger amounts of data on a regular basis.

Can the DSI EV0 and EVD nodes perform inline deduplication to avoid the extra capacity requirement?

We do allow the EV0/EVD to be configured for inline deduplication, but if the EV0 node cannot dedupe data as quickly as needed, subsequent jobs will then be placed in the VTL “landing space” (holding area) for post-process deduplication. We would still highly recommend having at least enough landing space to hold a single days’ worth of backups, if inline deduplication were not happening as expected. Please contact DSI Sales for assistance with properly sizing a solution for your specific environment.

Can we use IBM Storwize V5010 for the VTL repository? Is it supported? What performance do we need? How many disks?

Yes you can continue to use the V5010 that is in place today. We typically recommend configuring the landing space with flash or SSD, with standard rotational disks used for the (larger) repository.

To get an ESTIMATE of space required and recommended landing space, please refer to this page:

https://www.ibm.com/developerworks/community/wikis/home?lang=en#!/wiki/IBM%20Removable%20Media%20on%20IBM%20i/page/DSI%20VTL%20Sizing

I am an IBM reseller. How can I order Data Protection products from DSI?

All pricing and quotes are produced through IBM Passport Advantage. The specific part numbers are based on product, capacity and corresponding support term.

As an IBM reseller, what type of hardware do we need for DSI Software? Can you send us the hardware configuration?

DSI products ordered through PPA include hardware that is preconfigured. The only additional hardware that may be required is the desired storage array for use behind the VTL nodes. Typically an IBM Storage CTS will be able to assist in the configuration of the SAN attached storage in the DSI VTL node solutions.

DSI-D24: This is our appliance-based Enterprise Deduplication VTL solution that cannot be used with external storage. This appliance comes with the ability to support up to 24TB of deduplicated data on internal disk.

DSI-EVD/EV0: This is our enterprise Deduplication VTL node solution that requires external storage. This system does not include any storage, so Fibre Channel attached LUNs must be used to achieve the desired capacity for the environment.

How much faster is virtual tape than physical tape?

A high performance tape drive, such as LTO6, is rated at over 1.4TB/hr but with tape marks, I/O block size and systems utilization, these speeds are rarely if ever achieved. A DSI virtual tape system is built on a high performance RAID disk system with an average access time of 3-4 milliseconds. Because it is emulating tape, its performance characteristics are not the same. Tape marks and I/O starvation do not require the performance killing repositioning that actual streaming tapes require. A DSI virtual tape system is up to 25 times faster than the tape drives that it emulates.

Why is virtual tape a better choice than traditional (physical) tape?

There are several reasons that a virtual tape is a better solution than tape alone in a backup environment. Here are some of those reasons:
1. The DSI virtual tape is RAID protected. The virtual tape volumes stored on disk are ensured by disk I/O write protection and by RAID6 plus one data striping and mirroring.
2. Ensures backup/restore success by eliminating media/mechanical errors and manual intervention associated with traditional tape.
3. Remote offsite replication of virtual tapes provides disaster protection.
4. A virtual tape system centralizes management & consolidates backup resources.
5. Support for multiple concurrent sessions promotes faster backup and facilitates rapid data recovery.
6. Disk-to-disk is faster than traditional tape backup.
7. All DSI virtual tape solutions come standard with at rest encryption of physical disk drives.
8. Data movement between the virtual tape systems disk-based virtual tapes to physical tape media is accomplished as a secondary task; this process can be completed at any time of the day without impacting application performance.
9. Integrates seamlessly with existing backup software and policies.
10. Easy to deploy in your current network.

Will I lose data if a system has a catastrophic failure?

Redundancy is a major priority of our virtual tape solutions, including hot swap power supplies, hot swap and RAID6 protected backup hard disk drives, redundant fans, a spare drive and support for redundant controllers (with active-active failover). In the unlikely event of a catastrophic system problem, the data is still safe on the RAID protected (at-rest encrypted) drives.

Can I monitor the DSI virtual tape system with my SNMP monitoring software?

Yes. DSI virtual tape systems support SNMP monitoring programs and provide a MIB for download. All items monitored in the DSI virtual tape system are provided over SNMP (v2 and 3).

Will virtual tape work with my backup package?

Our virtual tape systems are tested with many backup systems including: Symantec, Legato, CA, Backbone etc. For all of these environments, the DSI virtual tape system appears as just another tape library and drives to the operating system.

Will virtual tape work with my Host Bus Adapter or Switch?

If a host bus adapter company (ATTO, Cambex, Emulex, LSI Logic, QLogic, Unisys, IBM) or server manufacturer makes a FC host bus adapter or iSCSI toe card to support open systems, then odds are we will work with it. If a switch company (Brocade, Cisco, Emulex, McData, QLogic) makes a Fibre Channel or IP switch for open systems environments, then odds are that we will work with that switch also.

Do I need a special driver or software to install your virtual tape system?

No. The DSI virtual tape systems will work with the standard drivers for the tape drives that are being emulated.

Do I need to modify my backup software to work with the virtual tape?

Our virtual tape solutions are engineered to be integrated with your existing backup environment, with little to no changes required.

How long has Dynamic Solutions International been in business?

Dynamic Solutions International was founded in 1973 and is on its fifth generation of virtual tape based systems. The company is not venture backed and operates without debt.

Do you have any competitors?

There are many manufacturers of virtual tape systems. However, we have over 50 years of data protection experience, and custom tailored backup and media management software for a host of mainframe platforms. With our experience and extensive support outreach. we are uniquely qualified to handle the demanding requirements of mission critical backup environments.

Do you sell DSI virtual tape systems in my country?

Almost certainly, unless you live in a country that is prohibited from buying technology products from U.S. companies. Even more importantly, because of our extensive partner relationships, our solutions are supported in most global locations. Please call DSI at 800-641-5215 or 1-303-754-2000 for specific questions regarding availability.

What backup tools are available?

Supports all IBMi backup tools and methods (ROBOT/SAVE, BRMS, LXI MMS, SAVLIB, media policies and IPL) without any process change.

Can I also use the VTL in my distributed environment?

Yes, DSI can support a mixed open system, IBMi, and mainframe environments.

Does the VTL support a bare metal system restore?

Yes. DSI ensures business continuity through IPL, bare metal reboot from virtual or physical tape.

How fast is the VTL?

The DSI VTL offers higher performance (write and restore) with connectivity across 16Gb/sec FC (fibre channel).

Does the VTL support tape consolidation?

Yes. The support for tape stacking allows multiple smaller virtual tapes to be consolidated onto larger physical tape media.

  • Dynamic Solutions International
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