Preferred configuration for HP DAT 72 drive

[john_fox]

Hi,

I have just installed a HP DAT 72 drive into our server running veritas backup exec 8.5.

I am trying to optimise the drive using the preferred configuration settings in the device properties dialog box.

I am trying to find out the settings for:
Block size
Buffer size
buffer count
high water count

I have read in the HP DAT 72 manual that the drive has an internal buffer of 8mb but in the buffer size for the drive it only goes upto 1024k.

Can anyone help as i cannot seem to find the settings anywhere.

Thanks in advance

[Kevin_Petersen]

Hi,

Is HP DAT 72 supported in version 8.5?

It seems like you have it running or..?

Thanks

Kevin

[Ken_Putnam]

To optimize throughput, you want the largest blocksize that you can specify, make the buffer at least twice the blocksize and number of buffers at least 5


For machines supporting a max of 64K block size, I use


BlkSize 64K
Buffer 128K
Number of Buffers 10

Just be sure that you have plenty of RAM on the media server. Also, as long as the buffers are never depleted, a larger total buffer will not speed things up at all, and will hold RAM back from the OS while a backup is running.

[Kevin_Petersen]

eh ok thanks

Do you also know if I can use a HP DAT 72 together with Backup Exec 8.5?

Kevin

[john_fox]

Hi Kevin,

Thanks for the help. Now you mention it the drive is only backing up a maximum of 35 gig per tape when it is supposed to be double that amount.

[Kevin_Petersen]

is that with or without compression?

Kevin

[john_fox]

yeah i had compression switched on.

[Kevin_Petersen]

35g with compression on??

Hmm not 100% supported I guess!

Not sure if I should buy a DAT 72...

Kevin

[Ken_Putnam]

Was that software or hardware compression?

if hardware, from the devices tab, right click the drive\properties, is "Enable Compression" selected"

is there a dip switch on the drive to enable hardware compression?

Try software only and see what happens

[Kevin_Petersen]

Hi fox1977

Did you get the compression working on the DAT 72?

Would you recommend a DAT 72 to be used with BE 8.5?

Thanks

Kevin

[Kevin_Petersen]

Hi again

How do I get Backup Exec 8.5 to recognize a HP DAT72i?

Windows Backup can use it without problems!

Thanks