Originally Posted by ruario
A checksum will tell you if a file is corrupt but it won't let you fix it. So, no that does not solve the problem at all. Did you read my linked post?
Fixing the problem involves having some redundancy either in the form of multiple backups on different media or at the very least parity archives. That way if you get some corruption due to media failure you may a different backup or use the parity files to have a chance to correct it.
Additionally I advise using internal compression on a file by file basis rather than external compression across the entire archive so that in the worst case you can recover some of your files (hopefully most of them). With ompression across the entire archive a minor corruption near the start of the file will probably mean that entire backup is a write off, due to the way compression works.
These are obvious things ruario. I only use my external on my mbp. It doesn't make sense to use external for your desktop unless you are out of drives and too dumb to put 1 in. But I think you are the one not reading what I wrote (or maybe you didn't check my last edit to go more into detail on what I meant). A checksum is the cure to the problem (as in knowing if your data can get backed up without problems). Also your data corruption due to compression argument is a small risk and can also happen to a non compressed tar (allthough much easily repaired). The better and more costly solution is like you said redundancy but I also added that in my last edit. Maybe you didnt get a chance to read my edited part? If you actually read what I wrote in there I'm pretty much on your side of what you wrote. I even agreed with what you wrote about bzip2.
Also using a SD Drive is pretty much the best option for this type of stuff. Both in speed and loss from fragmentation, or corruption.
But I appreciate your help.
EDIT before you correct me I realize what you meant by "External Internal Compression". But honestly this doesn't make a difference due to "CHECKSUM".
BTW this is my other Account I recently opened because I had forgot the password to the other 1 and lost access to that email. So JD = Mercury305