On Wed, Jan 28, 2009 at 3:23 PM, Dan Nelson <dnel...@allantgroup.com> wrote:
> In the last episode (Jan 28), Jaime said:
>>       /usr/bin/tar -cvpX /usr/local/etc/backups/skiplist-relative.txt -f 
>> /dev/sa0 -C / .
> If nothing else, I suggest bumping up your blocksize.  The default for tar
> (10k) is pretty small for modern tape drives.  Try -b 128 (for a 64k block
> size).  Another optimization would be to put a buffering program in between
> tar and your tape drive to decouple disk reads from tape writes.  misc/team,
> misc/buffer, and misc/cstream in ports are good for this.

Thanks.  Would this decrease the ability of other Unixes being able to
read the tape?  For example, using pax (which can read tar archives)
or GNU's tar?

Sadly, I forgot to mention something in my last message.  Sorry.

When reading from the tape using tar (bsdtar from FreeBSD 6.2 -- and,
yes, I'm preparing a cvsup as I write this :) ) the tape drive's Alarm
and Fault LEDs are lit up and then camcontrol devlist no longer shows
the tape drive.

After I wrote to the tape via a quick boot into Knoppix, I found that
FreeBSD's tar command could list the files on the tape.  So maybe that
is in the past now.  Maybe not.  I should have mentioned it earlier.

Any other thoughts before I try to OS update and the larger block size?

freebsd-questions@freebsd.org mailing list
To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"

Reply via email to