Job to Tape LTO4 Help!

[manuel.wagner]

Hy Guys,

Im using veeam b&r 7 to bakup my vmware esxi guests to local hdd of my backup server.
Then it should get backuped to a tape.

Therefore i am unsing a external HP StorageWorks 1840 tape drive connected via SAS.
The HP Ultrium LTO-4 tapes should have a capacity of 800GB / 1600GB 2:1 compressed.

My whole backup is about 750GB, in Veeam the Tapes are shown with a capacity of 781GB. When i make a Backup to tape, it tranfers about 570GB and then it shows the status "WaitingTape"?

What is "WaitingTape"? And why it only write 570GB? And can i use the whole 1600Gbs of the tape?

Its my first time using tapes with Veeam! I hope someone can help my.

Thanks!

[Vitaliy S.]

Hi Manuel,

Could the behavior you observe be similar to this one?

Thank you!

[manuel.wagner]

Hi,
Thanks for your answer.

In my case it's about over 20% less space. I think thats not normal?
And wahts about the 2:1 compression for 1600gb capacity? Is that possible with Veeam?

[Gostev]

In my case it's about over 20% less space. I think thats not normal?

May be normal for your device. Again, as explained in the above referenced topic, this is device-specific. You may want to check with your vendor directly. Or, we can do that for you, if you open a support case with us first.

And wahts about the 2:1 compression for 1600gb capacity? Is that possible with Veeam?

Sure it's possible, but this requires that you disable compression in Veeam jobs. Obviously, you cannot compress the same data twice
Disabling compression in Veeam is not recommended though, because it will result in reduced processing performance and no benefits.

[manuel.wagner]

Hy.

I have already openend a support case. And I have a fixed date for a remote maintenance to this backup server of my customer on tuesday.

Ok that means when i completely disabler Veeam compression and than i check "hardware compression" in the tape job --> it will use the 2:1 compression of the tape?

[Vitaliy S.]

Depends on the data you've backed up, but generally yes, you might have this ratio.

[manuel.wagner]

Do i also have do disable deduplication?
I have deleting the backups und now one full without compression is running..after that there should run the tape job with hardware compression!

Thank you!

[Vitaliy S.]

No, you needn't to that as your backups will be large with these two options disabled.

[tsightler]

When LTO devices quote their capacity they are generally quoting the 2:1 compression capacity and thus assuming you are going to send uncompressed data to the device. Since in this case Veeam is already backing up to a compressed disk file, and this pushing this compressed file to tape, you will generally not get significant compression from the hardware so the tape capacity is more like the "native" capacity of the device which, in the case of LTO4 is 800GB (probably why Veeam displays 781GB). I'm not sure why you are only getting 570GB to the tape as that feels a little low, but it's probably not realistic to expect to get anywhere near 1600GB.

[manuel.wagner]

okey..but as capacity there will be always only the 781Gb (800GB Tape) shown. Also when the drive use the 2:1 compression?

Yeah i know that i will never get the 1600gb, but i will be happy with 1000GB!

[tsightler]

okey..but as capacity there will be always only the 781Gb (800GB Tape) shown. Also when the drive use the 2:1 compression?

Yes, because that is the native capacity and Veeam will have no idea what the actual compression will be. If the data is compressed then it will use less native capacity, so for example if the data actually does compress and Veeam writes 800GB, it will still show 400GB native capacity free.

When sending compressed backups to an LTO4 device I wouldn't expect any additional compression at all.

[manuel.wagner]

support case# 00472740

Now i made a backup with the uncompressed backup (1,2TB).
Now it writes 880GB and then "waitingtape" again.

I also cleaned the tape drive. The HP Test Tool shows me a compression of 2,21:1 when it writes a test file of 1200MB.

[tsightler]

Is there any chance that it's an LTO3 tape in the drive? That would be about right 2.21:1 since an LTO3 tape is 400GB native 800GB compressed so 2.21:1 would be ~880GB. Just curious.

[manuel.wagner]

That would be the best solution^^

but no, its definitely a LTO4.
Today I changed the tape to try another one..i am sure thats LTO4..