Files to Tape Backup - Size

[ragesh@biosme.com]

Hello

We are taking veeam backup repostory backups to Tape media, what we observed is the backup job and data written on the tape doesn match. Data written on the tape is almost double of what the data size has been written as showing on the backup job.

We are using LT0-5 medias.

Any insights why the tape media is taking more space?

Thanks,
ragesh

[veremin]

What type of tape job are you using? Backup to tape or file to tape one? What backup mode do the source backup job leverage? How many backup files can be found on tapes after tape job's end ? Just one .vbk file or there is an additional one, by any chance? What product version are you currently at? Thanks.

[sderikonja]

I see this happening consistently but random at best. A job of 400 Gb will double to 800 Gb. In the end there are two full synthetic backups with one being recent while the other one could be from last month. It is hard to pinpoint as the dates are all over the place, yet not older than a month. This would not be so much of a problem if I did not setup the tape jobs not to exceed one LTO-5 tape. So does anyone know why it creates a synthetic backup from a month before?

[veremin]

What product version are you using? Is retention on tapes shorter than the one on disk? Also, are you leveraging virtual full backup as means to copy only latest full backup or rather as means to break forever incremental chain on tapes?

[sderikonja]

Veeam Version is 8.0.0.2084.
Tapes do not have a retention.
Backup to storage is forever incremental with synthetic full backup to tape.

[Shestakov]

Backup-to-tape with synthesized full backup requires at least double of .vbk size.
Please read the linked topic and ask additional questions if you have any.
Thanks.

[Dima P.]

Backup to storage is forever incremental with synthetic full backup to tape.

Could you please clarify the tape job schedule and synthesized full backup creation schedule (second step) you set for the said tape job? Thanks.

[sderikonja]

Backup-to-tape with synthesized full backup requires at least double of .vbk size.
Please read the linked topic and ask additional questions if you have any.
Thanks.

Where in this thread is size of .vbk specified? I do not see double mentioned anywhere. Please advise.

Could you please clarify the tape job schedule and synthesized full backup creation schedule (second step) you set for the said tape job? Thanks.

Source job (backup to storage) is set to run every 6 hours, Monday - Friday, between hours of 6am and 9pm, and on Saturday between hours 6am and 1pm.

There are two independent tape backup jobs. First is for onsite full synthetic, while the second is offsite full synthetic. Neither tape job includes incremental files or .vib

First tape job is set to run every week-night at 12:00am. Those tapes are never removed from the drive, which by the way, is a Dell Power vault 124t.

Second tape job is set to run Mondays and Thursdays at 9:45am.

[veremin]

Tapes do not have a retention.

Do you mean never overwrite data option is enabled?

In the end there are two full synthetic backups with one being recent while the other one could be from last month.

Usually, it happens when the .vbk was copied to tape, then, after some time got removed from it, thus, backup server decided to copy the old file anew. See this thread for additional information.

Thanks.

[sderikonja]

Do you mean never overwrite data option is enabled?

Negative. "Do not protect data(cyclically overwrite tapes as required) is enabled.

Usually, it happens when the .vbk was copied to tape, then, after some time got removed from it, thus, backup server decided to copy the old file anew. See this thread for additional information.

This makes sense as I have a retention of 30 days set for forward incremental and no retention for tape media.

[veremin]

Yep, that's what I was trying to point out. Just make sure that tape retention is longer than the disk one; should help you to avoid the said issue.

If you're only copying full backup files, you'll be glad to hear that in version 9 we will add the ability to always copy only the latest full backup.

Thanks.

[sderikonja]

If you're only copying full backup files, you'll be glad to hear that in version 9 we will add the ability to always copy only the latest full backup.

I thought V8 had that feature all along. Few months ago I created a support ticket to help me with initial setup of Veeam and tape backups. A tech explained that only latest full backup will be copied to the tape.

Thanks for the help though.

[Shestakov]

When you run backup to tape for the first time, it asks you if you want to copy only latest chain or all files. However if you have several .vbks created by the source job between backup-to-tape runs, it will always copy all missing files.
Here is the related discussion.

[veremin]

Nikita is right here, most likely, support engineer meant this option. However, even with this option if some portion of chain has been copied to tapes, then, deleted, backup server decides to copy it again, as long as it exists on disk.

That won't be the case with Version 9 that will allow to always copy only the latest full backup.

Thanks.