fbackup

[A.G.M. Velthof]

I want to make the backup over the network and use:
fbackup -i /files -f -|remsh machinename dd ibs=64k obs=32k of=/dev/rmt/1m.
So far it works fine.
When I want to recover some files, I use:
remsh machinename dd ibs=32k obs=64k if=dev/rmt/1m|/usr/sbin/frecover -xv -i /files -f -
Some file are recovered correct but some of them gave an error:
"file trailer does not match file header" and also "block checksum mismatch"
Anyone any idea?

[Darren Prior]

Hi,

The more usual method of using fbackup with a remote tape drive is:

fbackup -i /files -f machinename:/dev/rmt/1m

Is there a special reason why you are using remsh and dd?

regards,

Darren.

[melvyn burnard]

are both systems HP-UX? If so, why not just use fbackup to hte remote system?
i.e.
fbackup -i /files -f remotenode:/dev/rmt/1m after putting in a .rhosts entry in the remote host

[RAJESH GANGADHARAN]

Hi
Insted of using remsh and dd you can directly use the remote tape drive. eg:
fbackup -f remotehost:/devicefile.


-Rajesh

[A.G.M. Velthof]

The reason why I piped the fbackup to dd is the speed.
I always used fbackup -i /files -f machinename:/dev/rmt/1m but the total backup time increased to 20 hours.
With the help of dd the total time is 7 hours.

[melvyn burnard · Accepted solution]

Have you looked at tuning hte fbackup config file?
This may help in reducing hte time. I would look at the blocksperrecord, records,readerprocesses to start with.
You would probably want to do the changes on both systems to se e if it does help

[A.G.M. Velthof]

No I did not do that.
I will play a little with the configfile and let you know what the result will be.

Alfons

[Bill Hassell]

No matter whether you use a local or remote tape drive, a config file is imperatrive since the defaults for fbackup are badly out of date. This file is suitable for DDS, DLT and Ultrium tape drives:


blocksperrecord 256
records 32
checkpointfreq 1024
readerprocesses 6
maxretries 5
retrylimit 5000000
maxvoluses 200
filesperfsm 2000

Note that when you use a remote tape drive (whether using dd or fbackup's built-in remote tape capability), you lose searchmarks, the ability to place highspeed searchmarks onto the tape. Fast searchmarks will allow restoration of a specific file or directory within a few minutes rather than a serial read through the tape. For effective network backups at very high speeds and reliability, you should look at commercial products such as HiComp's HiBack product, or HP's OpenView Data Protector (aka, Omniback). These products handle network backups, support tape changers, can push data to parallel tape drives, recover from media errors, etc.