power vault 114t tape drive write error

Hi Guys,

I am trying to implement bacula backup and i am having very big problems.I am having 10 client for my backup server it will run backup 4 or 5 client fine and then my volume status is changing to full because of the following error

30-Mar 15:38 backup01-sd: NightlySave1.2006-03-30_15.21.00 Error: block.c:552 Write error at 5:6714 on device

/dev/nst0. ERR=Input/output error.
30-Mar 15:38 backup01-sd: NightlySave1.2006-03-30_15.21.00 Error: Error writing final EOF to tape. This tape may

not be readable.
dev.c:1213 ioctl MTWEOF error on /dev/nst0. ERR=Input/output error.

 

and

 

30-Mar 12:14 backup01-sd: NightlySavewww01.2006-03-30_11.50.00 Error: block.c:552 Write error at 6:6478 on device

/dev/nst0. ERR=Input/output error.
30-Mar 12:14 backup01-sd: NightlySavewww01.2006-03-30_11.50.00 Error: Backspace record at EOT failed.

ERR=Input/output error


can some one help me why my backup is not completting and the solution for this problem

i am running dell power vault 114T tape drive with debian sarge kernel version 2.4.27