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-   -   which backup medium do you prefer? (https://www.linuxquestions.org/questions/linux-general-1/which-backup-medium-do-you-prefer-797415/)

cantab 03-26-2010 04:32 AM

Quote:

Originally Posted by newbiesforever (Post 3912489)
This is a tangential issue, but almost as bad as losing all access to my data is having someone else possess a copy of it, with no way to even erase it. I wish there were some gadget that could remotely instruct a stolen hard drive to erase itself.

Use encryption. Provided your password is strong enough, your computer or USB drive isn't hacked or (surveillance) bugged, and the algorithm isn't cracked, nobody is accessing your data.

As for backups - many people speak against optical media, but I believe they are the only commonly used storage medium to have lifespan ratings. High quality media stored correctly ought to easily keep for a decade.

Of course, discussions of lifespan are more to do with archival as opposed to backup. A backup only has to last until the next full backup. In theory it would seem preferable to replace the medium as often as possible. If your critical data quantity will fit on DVD-R that would seem to be a good choice.

H_TeXMeX_H 03-26-2010 07:44 AM

Quote:

Originally Posted by newbiesforever (Post 3912489)
Please elaborate on this. I assume you mean a flash drive that fails can never be fixed or accessed again.

Since I am interested in keeping another backup medium in case of the computer (and possibly other electronics nearby) being stolen, a flash drive would be better than a CD or some kind of portable hard drive, because it's smaller, easier to hide, and less recognizable.

This is a tangential issue, but almost as bad as losing all access to my data is having someone else possess a copy of it, with no way to even erase it. I wish there were some gadget that could remotely instruct a stolen hard drive to erase itself.

Yup, that's what I mean. Once a USB drive fails, which I might add happens suddenly and without warning, there is NO way to get your data back. Once it's dead, it's dead. With a DVD, even if it's scratched you can get something, and with dvdisaster you can recover all your data.

I would encrypt the HDD if that's what you fear, especially sensitive data if you don't wanna do the whole HDD.

Larry Webb 03-26-2010 08:03 AM

For the price and reliability external hd is the only way to go. The main problem I have had with backups is the dedication to back up on a regular schedule. I lost a laptop that I used maybe once a week that I had not backed up for about 6 months. There were a lot of pictures lost.

i92guboj 03-26-2010 08:31 AM

Quote:

Originally Posted by Larry Webb (Post 3913219)
For the price and reliability external hd is the only way to go. The main problem I have had with backups is the dedication to back up on a regular schedule. I lost a laptop that I used maybe once a week that I had not backed up for about 6 months. There were a lot of pictures lost.

That's what cron jobs are for. You only have to worry to plug the media. You could even script it via udev so the backup script is run when you plug that concrete disk.

H_TeXMeX_H 03-26-2010 09:59 AM

Also remember to use smartctl on all your HDDs to perform a long test once every few months, it will usually tell your ahead of time when a drive is likely to fail, so then you know to backup.

newbiesforever 03-26-2010 11:46 AM

Quote:

Originally Posted by cantab (Post 3913021)
Use encryption. Provided your password is strong enough, your computer or USB drive isn't hacked or (surveillance) bugged, and the algorithm isn't cracked, nobody is accessing your data.

As for backups - many people speak against optical media, but I believe they are the only commonly used storage medium to have lifespan ratings. High quality media stored correctly ought to easily keep for a decade.

Of course, discussions of lifespan are more to do with archival as opposed to backup. A backup only has to last until the next full backup. In theory it would seem preferable to replace the medium as often as possible. If your critical data quantity will fit on DVD-R that would seem to be a good choice.

It would still be out there, and I'd never know. A hacker would have all the time he or she wanted to chip away at it. I'd feel like my best friend did when her flash drive was stolen due to her carelessness. I'd be tormented.

cantab 03-26-2010 12:02 PM

Quote:

Originally Posted by newbiesforever (Post 3913453)
A hacker would have all the time he or she wanted to chip away at it.

He's gonna need all the time. John Callas, of PGP corporation, wrote:

Quote:

Burt Kaliski first came up with this characterization, and if he had a nickel for every time I tell it, he could buy a latte or three.

Imagine a computer that is the size of a grain of sand that can test keys against some encrypted data. Also imagine that it can test a key in the amount of time it takes light to cross it. Then consider a cluster of these computers, so many that if you covered the earth with them, they would cover the whole planet to the height of 1 meter. The cluster of computers would crack a 128-bit key on average in 1,000 years.
And that's a 128 bit key. Most ciphers now use 256 bits - which isn't twice as strong, it's a hundred trillion trillion trillion times stronger. And there's always 'cascade' encryption to further lengthen the key as well as insure against any one algorithm having its security reduced.

Since you will probably bring up quantum computers - currently it's though they will only reduce the security to half the key length. So a quantum computer will have as much trouble breaking a 512 bit key as a classical computer has breaking a 256 bit one.

If someone accesses encrypted data, it will almost certainly be because they obtain the password from you, or they hack into the computer you use to work on the encrypted data.

newbiesforever 03-26-2010 12:14 PM

Quote:

Originally Posted by cantab (Post 3913480)
Since you will probably bring up quantum computers

No, I won't. :D You mistake me for a nerd, which I no longer am, and you probably missed my point. Encrypted or not, my data would be out there somewhere, and I could never get it back nor make entirely certain of its falling victim to human ingenuity. If you're still too rational to understand my problem, you Linux experts must be unfamiliar with neuroses.

H_TeXMeX_H 03-26-2010 12:33 PM

If you encrypt your data with a good encryption algorithm and a good password, they will only have a chance of succeeding if they have a supercomputer at their disposal ... i.e. the gubmint, but I doubt even they could break the higher end algorithms, or it would take them a long time, years, I don't think they would waste their time.

moxieman99 03-26-2010 12:44 PM

Backup medium. That's when you go to Madam Olivari because you can't find your ouija board, right?

dv502 03-26-2010 01:01 PM

I use an encrypted usb flash drive to store very important files such as my password list, database files and spreadsheet files.

And for miscellaneous files such as videos, music and etc I use an external USB drive backup via the rsync command.

newbiesforever 03-26-2010 03:06 PM

Quote:

Originally Posted by moxieman99 (Post 3913526)
Backup medium. That's when you go to Madam Olivari because you can't find your ouija board, right?

I don't need a medium. I've belonged to the Church of Knowledgology (and I mean belonged) ever since it taught me about my past lives. I was once the janitor in a spacefaring crew of intelligent cacti.

frieza 03-26-2010 03:12 PM

Quote:

This is a tangential issue, but almost as bad as losing all access to my data is having someone else possess a copy of it, with no way to even erase it. I wish there were some gadget that could remotely instruct a stolen hard drive to erase itself.
actually there is
http://www.deadondemand.com/products/enhancedhdd/

H_TeXMeX_H 03-26-2010 03:33 PM

Quote:

Originally Posted by frieza (Post 3913670)

Hey, cool, that might be useful, thanks :)

cantab 03-26-2010 06:10 PM

Quote:

Originally Posted by frieza (Post 3913670)

Interesting...however, I see a couple of problems. One is you can be notified when it's released, which means it isn't out now, which means it may well be vapourware. The other is, what if the triggers can't reach the drive? Maybe some will be selfdestruct in absence (of say, a special signal your computer sends the drive), but then - and indeed in any case - the risk of a false trigger makes it unsuitable for backups.


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