Jean-Louis Martineau wrote:
> Are you sure of the size of your tape? 4Gb is with compression or not, 
> Do your data are compressible or not, are you using software compression?
> 
> Jean-Louis
> 


The amount of data I backup every day is about 3.6 Gb. During the first cycle 
when the tapes have just been labelled, it works fine. The problem arises when 
an tape has to be overwritten.
I guess it means the size of the tape is not the problem.
The tape I used are 4Gb without compression.
The compression is turned off with the command
mt -f /dev/nst0 compression 0
I added this line in the rc.local to be sure compression is turned off after 
reboot.

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