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zolteckx6
I have been using tar for quite a while but not for any Dir backups. Now I am trying to back up a Dir full of instrustional videos with tar -cvjf and the tarball I get back is the same size as the Dir without compression. Even if I omit the -j compression type the archive is the same size....Is this normal behavior for a dir full of mp4 files? Also (and I know tar may not be the best for backups ) but I was warned about using bz2 compression because "if the archive gets currupt anywhere in the archive I will not be able to open the archive from the point of corruption; However with regular tar compression I could save most of the archive except the block that is currupt "...Is this correct?

Thankyou for any input smile.gif

I did find this:
You can use the `bzip2recover' program to attempt to recover
data from undamaged sections of corrupted files.

so that answers the bz2 question but the man seemed pretty concerned about using this function on a tape drive...
michaelk
Welcome to LinuxHelp.

Yes it is normal. Binary files really can not be compressed much if at all. In fact it is possible that the compressed binary file could be bigger then the original.
With writing binary data to tape you could dump the entire file to hard drive and then run the recover program but since you are- not going to save any space anyway I would not bother using compression.

For error recovery check out this URL.
/www.bzip.org/1.0.3/html/recovering.html
zolteckx6
QUOTE (michaelk @ May 26 2014, 03:57 PM) *
Welcome to LinuxHelp.

Yes it is normal. Binary files really can not be compressed much if at all. In fact it is possible that the compressed binary file could be bigger then the original.
With writing binary data to tape you could dump the entire file to hard drive and then run the recover program but since you are- not going to save any space anyway I would not bother using compression.

For error recovery check out this URL.
/www.bzip.org/1.0.3/html/recovering.html



Thank you, that was exactly the answer I was looking for.
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