Re: apps Re: Question on backups using rsync
On Wed, Dec 21, 2005 at 06:36:23PM -0800, Alvin Oga wrote:
> if you don't trust find|tar ... you have major problems with the machine's
> reliability and these brand new commands nobody used for 30 yrs :-)
> using any other "favorite backup programs" will suffer the same fate of
> losing "huge amounts of data", and more importantly, is there a way to
> recover the lost data and/or alternative apps that doesn't have the "bug"
> or just simply fix the hardware ..
> - there is nothing sw can to fix flaky hardware .... and unreliable
> hardware cannot be used as a means to invalidate "methodology"
> - good methdologies would already acocunt for the various hundred
> ways that it can fail in the first place
That's exactly what I'm saying: your tar | gpg methodology has not accounted
for the chance of a few flipped bits, because if it had, it wouldn't lead to
massive data loss, which it does. Compressing/encrypting after archiving is
inferior to compressing/encrypting before archiving when considering
robustness. I just can't comprehend how you could dispute that.
> > I'm open to hearing any advantages of tar over afio for backups, because I
> > don't know of even one.
> i will bet any amount of $$$ and data .. that find | tar is better than
> the average "backup specific apps" that meets all my backup requirements
> my backup specs
> - it will NOT corrupt my prev backups, say going back 5 years
> - it is fast and is live with the simple change of an ip#
> and untar as needed depending on the purpose of that tar files
> - confidential data is encrypted and root read only
> - i can restore to any random data and random time at any
> time somebody says "prove that it can be done"
> - it can support 20Terabytes of data in a 4U chassis ... and
> obvisously, that data is also backed up ... i keep at leaast
> 3 copies of everything in various state of readiness
> - it doesn't costs more than the bare costs of the hw in both
> labor to write or test the "program" and methodology
> - it must survive a failure of 2 successive full backups
> ( ie have a work around backup failures )
> - bare metal restore should be done in a matter of few minutes
> except that "restore" of 10TB sized data will take a FEW seconds
> - backup system must also be flexible and extensible and
> can support 180degree methodology changes
> ( managers are known to change directions ya know and budgets
> come and go randomly )
> - and it obviously has to be searchable
> - some people like gui's... but i think gui's is for windoze kids
> - more detailed specs... and semi endless list of major points
> - find | tar meets all those specs above ...
> and trivially scriptable and anybody can maintain it since
> it's not wirtten in martian code, even if it might loook like it
> after a few dozen people add their $0.01 to it
afio is no more of a "backup specific app" than tar is. afio has had no more
code changes than tar in the last 5 years. I'm guessing you don't know
anything about it based on your comments.
I still don't see anything in that list that tar has but afio doesn't. I *do*
know one thing that afio has that tar doesn't: much greater robustness in the
case of corruption. Whether you "trust" your hardware or not, it doesn't make
sense to me to choose a less robust solution over a more robust solution.