ArcServe and VTLs/Tape Libraries

[Russell5]

We're looking to implement a VTL and Tape Library into our backup environment. In order to push enough data to maximize the thruput on the VTL, it looks like we'll need multiple backup servers with several GigE network cards in them.

Does anyone else have a similar setup, or have any thoughts on how ArcServe can be configured so that two backup servers can talk to the same library? Other software, such as CommVault I believe, has the concept of a master server that does all the communications to the VTL and library, and the child servers route all commands through the master. I haven't heard of this existing in ArcServe, so I'm not sure if our proposed setup is even possible.

 

[Cyklops]

You can use ARCserve for disk staging (backup to disk with a copy to tape) but I would not recommend using a VTL. You can make it work by installing several ARCserve servers and share the VTL using the SAN option but the copy to the 'real' tape library has to be initiated either by the VTL in the backupground (so ARCserve doesn't know that an extra copy of the backup data is made) or through the ARCserve command line utility tapecopy (which has to be scripted and scheduled). If you are using disk anyway for backup purposes (which a VTL in fact does) let ARCserve do the staging part and forget about the VTL.
With CommVault, which has a totally different approach towards backup and restore, this can be done flawlessly.

regards

 

[Russell5]

I appreciate the response Cyklops!
The reason why we're leaning towards a VTL solution as opposed to pure disk is the built in hardware compression and ease of administration. We love tape libraries because ArcServe handles the tape movement, with the rotation it knows to put fulls in one tape and differentials on another. With a VTL, we can keep multiple weeks worth of backups and let the rotation scheme handle where all the data goes. We simply point all the backups to one library and let ArcServe do the rest.

With pure disk, we'd have to create multiple file devices and have certain backups going to certain devices, and other backups going to other devices depending on how long we want to keep them. From an administrative standpoint, this doesn't seem a great way to go, especially considering the fact that we're a large company without anyone fully devoted to backups (it's being shared by multiple individuals who's primary role is not backups). Although I do realize it’s possible to do with a pure disk solution, I want to make this as easy as possible on the administrators and we’re willing to pay a little extra for the convenience.

To answer the point in your post regarding using the tape copies, we were thinking of using post scripts after the backups were completed to kick off the tape copies. I really wish there was a way to use the ArcServe Disk Staging option, or something similar, to the VTL so that you could see the tape copies going within ArcServe.

If I'm understanding this incorrectly, I'd love to hear your take on it.

 

[davidmichel]

ARCserve has a SAN option for sharing a tape library.

However ck to see if the VTL can be configured into two virtual libraries, some virtual and physical tape libraries do support this. In other words you have one physical unit that can be divided into two so that each backup server thinks it has its own and can not see the drives or slots configured for the other.

By the way the latest revision of tape drives have a higher throughput that most tape drives so it is not a given that a VTL is faster. Most clients that I have worked with use a VTL for quick restores.

 

[Russell5]

DR and quick restores is one of the main reasons why we're looking to implement a disk based solution. The confusion comes from which disk based solution to implement. Do you go with a VTL, basic attached disk, or a data deduplication appliance like Data Domain offers? If a full backup is around 15TB, we need a solution that is scalable, fast, cost effective, and easy on the administrative side. From our research, we found that a VTL is easier on administration, but higher on cost. Basic disk is good on cost, but higher on administration.

In your opinion, what you have found most companies using when it comes to a D-D-T based solution, especially in those companies that use ArcServe?

 

[davidmichel]

The clients that I have worked with that had that much data used it as a virtual tape library either with a single ARCserve server, or split as mentioned above, or in a SAN configuration all depending on the details of their setup. Then from backup to the VLT the data is moved to tape for long term storage.