VMware Backups running slow on tape drives and Disk

[Iype]

Hi, have a problem in running backups to tapes drives, as its going very slow.

We have a VM proxy media server with 6 IBM tape drives zoned to the server.

VM proxy media server configuration is 2008 R2. we have 8gp sfp also installed. This media server is used to take only VMware backups using the vstorage api.

2 copies are taken at a time for each VM servers. The backup take to tape is running slow so we are not able to finish the backup within SLA. I need to know if there is any parameters that we need to set to increase the speed of backup when taking to tape drive. The tape drives are running with the latest IBM tape drive version, still we dont see any increase in performance.

Currently we have only 2 parameter set for the windows VM media server:

NET_BUFFER_SZ = 10485760

STAGING_JOB_KB_LIMIT = 99614720

Can you let me know what parameters and values need to be set for windows 2008 R2 server.

[Nicolai]

Take a look at the NUMBER_DATA_BUFFERS / SIZE_DATA_BUFFERS. These setting can improve tape performance. However VMware tuning is tricky task so expect to tune elsewhere.

http://www.symantec.com/docs/TECH1724

http://www.symantec.com/docs/TECH19206

http://www.symantec.com/docs/TECH18422

Take a look at the NetBackup 7.1 Backup Planning and Performance Tuning Guide also. It a good source of tip and tricks.

http://www.symantec.com/docs/DOC4483

[Dyneshia · Accepted solution]

Please see : IA B29: Best Practices for Backup and Recovery of VMware

https://www-secure.symantec.com/connect/sites/default/files/IA%20B29%20-%20Best%20Prac%20Backup%20%20Recov%20VMware_EM_0.pdf

And this excellent forum

https://www-secure.symantec.com/connect/forums/very-slow-vm-backups#new

[Iype]

Hi Dyneshia, just went through the TN: but i would like to know what values would be best for our environment.

I have given, for which backup was going in a good speed

NUMBER_DATA_BUFFERS = 256

SIZE_DATA_BUFFERS = 262144

But not sure if above settings will impact the system performace.

Tape Drive Parameters details:[IBM LTO5 tape drives]

Maximum block Size = 8388608 

Minimum block size = 1

Default Block size = 65536

Media server details:

CPU Type: Intel(R) Xeon(R) CPU E5649 @ 2.53GHz 

Clock Speed (MHz): 2533 

Number of logical CPUs: 24 

Installed Memory (MB): 16374 

Operating System:  Windows / Windows 2008 Enterprise R2 x64 

Total Tape drives: 6
Multiplexing : 16 per/drive

Can you help in how to identify the required values for the environment.