I need guidance on how to resolve the following issue: I have 61 backup policies for 101 clients that are being written directly to our VTL. All backup policies were configured for multiplexing level 4. I recently disabled multiplexing for all backup policies. Soon thereafter, a lot of our backup jobs began failing with status code 196, client backup was not attempted because backup window closed. Our Diligent VTF Open appliance currently run 3 jobs at once, the rest are put in a queue, is it possible to write to more virtual tapes to speedup our backup times and thus reduce status code 196 errors? Regards, James

> is it possible to write to more virtual tapes to speedup our backup times and thus reduce status code 196 errors? Without MPX, it may possible if you prepare an configure enough drives on VTL.Then, as simpsop wrote, increate Max Concurrent Drives of your storage unit(s). I guess your current configuration is 3 virtual drives without MPX. Your first configuration is 3 drives with 4 MPX, so your four first config can perform 12 writes at a time. Right? If so, my recommendation for non-MPX write is to add 9 more virtual drives on VTL and set maximum concurrent write drives to 12.

Status Code 196 errors

rjrumfelt
Level 6
15 years ago
your multiplexing?

If it was not causing a big issue with your restore times, I would add the multplexing back into your environment.
jackja
Level 3
15 years ago
Hi rjrumfelt,

I was told that this wasn't a recommended best practice because this can cause data fragmentation when writing directly to disk.
rjrumfelt
Level 6
15 years ago
virtual drives are you writing to?

And what are the following attributes set to?

max_jobs_per_client

and then under your policies:

"limit jobs per policy"

and I'm not familiar with diligent appliances - can you tune the number of concurrent jobs attribute?
Nitesh
Level 4
15 years ago
Please check suggest by rjrumfelt..

it will helpfull for u

And set media multiplexing above to 15 in policy

Thanks..
fieldnmultistre
Level 3
15 years ago
We utilize vlt in our setup, and have multiplexing set to 1+ number of clients in policy. So far we have not seen issues with framgentation
pdsimpson
Level 3
15 years ago
We are also using a VLT, emulating 24 drives.

I set "Max Concurrent Drives" to n-2 under the Storage menu, which allows me 2 open drives for restores / etc.

Bump up your "Max Jobs per Policy" too
jackja
Level 3
15 years ago
So, is it true to say that since my VTL (VTF Open) appliance doesn't support deduplication feature, multiplexing in this case would not cause fragmented data on my VTL?
Yasuhisa_Ishika
Level 6
15 years ago
Which is better, some unfragmented backups with many unsuccessful backup, or all backups successfully end?
Fragmentated backups on physical tapes affect the restore perfomance, but not so much on VTL, in general.
Yasuhisa_Ishika
Level 6
15 years ago
> is it possible to write to more virtual tapes to speedup our backup times and thus reduce status code 196 errors?

Without MPX, it may possible if you prepare an configure enough drives on VTL.Then, as simpsop wrote, increate Max Concurrent Drives of your storage unit(s).

I guess your current configuration is 3 virtual drives without MPX.
Your first configuration is 3 drives with 4 MPX, so your four first config can perform 12 writes at a time. Right?
If so, my recommendation for non-MPX write is to add 9 more virtual drives on VTL and set maximum concurrent write drives to 12.
jackja
Level 3
15 years ago
Hi Yasuhisa,

I have my maximum concurrent write drives set to 4. In my tape library I am currently using 4 licensed physical drives. Now, If I reconfigure my VTL to use 12 virtual drives and change the maximum concurrent write drives to 12, how will this change affect the jobs written directly to physical tape?