topic Re: Fbackup in Operating System - HP-UX

Fbackup

Paramvir — Mon, 09 Jul 2007 04:42:21 GMT

Hello All,

Can anybody confirm me that fbackup taken through SAM is compressed or not.

If not is there any option expect from hardware.

Regards,

Paramvir Bhardwaj

Re: Fbackup

V. Nyga — Mon, 09 Jul 2007 04:54:02 GMT

Hi,

it depends to your configuration.
Compression is only set by choosing the right device file.
Check /dev/rmt:
Ending with 'BEST' is with compression.
Either you choose this one in SAM or see if '0m' is configured like '*BEST'.
For example at my server:
crw-rw-rw- 2 bin bin 205 0x020000 23. Juli 2004 0m
crw-rw-rw- 2 bin bin 205 0x020000 23. Juli 2004 c2t0d0BEST

So I can choose either c2t0d0BEST or 0m, both will compress.

crw-rw-rw- 1 bin bin 205 0x020001 23. Juli 2004 c2t0d0DDS - will not compress.

HTH
Volkmar

Re: Fbackup

Bill Hassell — Mon, 09 Jul 2007 07:05:10 GMT

As mentioned, fbackup does not control compression, the device file enables compression. There are very few device files in /dev/rmt that are NOT setup for compression. To see the options for each device file, use lssf:

lssf /dev/rmt/*

If you are using /dev/rmt/0m, then it is compressed -- the words "best density available" means that this device file will enable compression. NOTE: compression is only effective with highly repetitive patterns such as massively large text files and partially filled databases. A backup of just vg00 will average about 1.2:1 to 1.6:1 compression, nowhere near to the 'marketing' value for tape drives which is 2:1. If you plan for the only native capacity of the tape, then you won't be disappointed.

Re: Fbackup

Paramvir — Thu, 20 Jan 2011 22:52:16 GMT

Thanks.....