topic Re: Copying volumes to tape in Network and Storage Protocols

Copying volumes to tape

nigel_foley — Thu, 05 Jun 2025 06:55:15 GMT

I have a customer asking about connecting a tape drive directly to a filer. They want to copy CIFS volumes to a tape drive using ONTAP utilities rather than NDMP based backup software. Has anybody any experience of doing this? Are there any gotchas to be aware of?

Re: Copying volumes to tape

scottgelb — Mon, 09 May 2011 07:00:28 GMT

dump and restore commands... for example "dump 0fn rst0a jobname /vol/vol0" but you have no robot control, so you have to change tapes manually or find an old library that supports stacker mode. And there is no direct access restore, so all tapes in a backup set have to be mounted and read prior to restore of file regardless of which tape the file resides. I would try to sell them SnapVault and keep dedup retention on disk...manual dump backups won't be easy to maintain.

Re: Copying volumes to tape

shaunjurr — Mon, 09 May 2011 07:49:21 GMT

*lol* ... I did this for a customer once... from a FAS250 with a hacked HSSDC to fibre (+ 12V DC converter from the local electronics store) to a small Storage Tek tape library in stacker mode. Basically, the customer wouldn't listen. They had to go through the pain of burning out the fibre converter a few times and a few impossible restores before they finally broke down and did backup in a way that assured verifiable results and restores... Basically, it's just a bad idea, but I'm guessing your customer is just as stubborn. I guess you can be happy that you don't have HSSDC connections on your filer. The bad part is that you basically also need one tape library per filer as well. Not exactly a good way to save money because it just doesn't scale. If you have any chance, get them to pay for services rendered and run as far away as you can, hehe.

Good luck.

Re: Copying volumes to tape

mcope — Mon, 09 May 2011 14:39:00 GMT

Even if they do manage to get the tape drives directly attached, they won't gain anything by not using NDMP. The only native backup utility in ONTAP is 'dump' and if you look at the NDMP backup process, it's just using dump. As mentioned in another reply, NDMP gives the user the ability to manage the tapes. If the customer is looking to avoid spending money on a backup application, there are open source Unix/Linux backup applications. However, most use NDMP...and believe me, you get what you pay for - especially when it comes to doing restores. Most people look at backup applications and only consider how fast and reliable the backup is. Backup applications need to be evaluated on the difficulty, reliability, and time-to-recover it takes restore data because that's what you buy them for.

Re: Copying volumes to tape

nigel_foley — Tue, 10 May 2011 11:13:15 GMT

Hi Scott,

Thanks for your comments. I'll try and get them to look at SnapVault as a better alternative.

Re: Copying volumes to tape

nigel_foley — Tue, 10 May 2011 11:18:20 GMT

Hi Shaun

The customer is very unix literate and think they will save money on backup software. All the responses suggest their thinking is flawed! Thanks again for your comments.

Re: Copying volumes to tape

nigel_foley — Tue, 10 May 2011 11:21:26 GMT

Hi Michael

Thanks for your comments. Much appreciated.

The time to recover argument is quite valid and may strenghthen the case for using SnapVault.