fbackup takes hell lot of time.

[Amruth]

Hi,

In a new L-class server the fbackup is giving very slow response. What can be the reasons ? HP-UX 11.00 is loaded and all other things are found ok. Uses a drive DSS-#. IF anybody can please reply about the speed of DDS-3 that's the transfer rate ?

thanks..
AR

[James R. Ferguson]

Hi:

It is likely thay you need to specify more efficient 'fbackup' configuration parameters. See my comments, along with Bill Hassell's, and the Technical Knowledge Base document, #B00000196, attached to this thread:

http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xc5f35e938a10d6118ff40090279cd0f9,00.html

Another possibility is that you have inuse files during the backup. 'fbackup' will note the modification timestamp of files when it begins copying to tape and when it has finished the transfer from disk. If the timestamp of the file is noted to have changed, 'fbackup' will mark the current tape image "bad" and proceed to recopy the file. This will occur up to 'maxretries' as specified in 'fbackup's configuration file. Not only are retries time consuming (!) but very wasteful of tape (!).

Regards!

...JRF...

[harry d brown jr]

AR,


Are you doing a full backup? How much disk are you backing up? What SCSI chain is your tape drive on? Are there any other devices on that scsi chain? Is the system under moderate or heavy use during the backup?

here's the dds3 info:
http://www.products.storage.hp.com/eprise/main/storage/DisplayPages/summary.htm?DataPage=dds3-dat24

live free or die
harry

[James R. Ferguson]

Hi (again):

One further comment. Set the 'readerprocesses' of 'fbackup' upwards. The default is two (2), but six (6) are allowed. The higher the number the more concurrent processes read data to deliver to the tape. Too low a number may result in the tape drive falling in and out of streaming mode thereby reducing copy times significantly.

See the man pages for 'fbackup' for more details on the 'config' file.

Regards!

...JRF...