Solved Compressing files to move to External HD

[Senteaf]

Hello. I want to add a compressed file(preferably free so I choose 7zip...) to my external HD, I am not sure right now whether I just want to "store" or "compress".

I wonder if there are any risks of file corruptions on my external HD.

Does compressing increase the risk? Based on my experiences I have come across many compressed archives that corrupted over time.


Thank you!

 

[bobafetthotmail]

what are you going to compress? What did you use to compress the files that got corrupted over time?

afaik, archives are just a file like another, so they have the same chances of getting corrupted of any other file. I have plenty of compressed files, and none got corrupted in nearly a decade.

I'm a fan of Peazip as it has a better interface than 7zip.

 

[Senteaf]

Your Grace,
I am going to compress a huge folder of many different file's formats.

I think I will try Peazip, because you said they are lasting for decades.

Thank you!

 

[bobafetthotmail]

ehm, wait a second. Peazip can compress your files in various ways, and create different kinds of archives depending on setup. The most reliable ones (imho) are the rar and 7zip archives (as both date back decades and actually lasted decades). Not that others suck, but I never used them.

Also check the compression options, as all compression programs can decrease the quality of images and movies to shrink the size of the file, and you usually don't want that.

 

[Senteaf]

Umm
I see.

I don't think this kind of compression is the kind that you would call lossy. The images and movies are already compressed in the first place. 7zip compresses it in size, not quality.

 

[bobafetthotmail]

Some compressing programs like say WinRar (that I used before Peazip) did offer me to shrink the images and movies by using lossy compression (that is by decreasing quality). THat's because shrinking the size of a movie or an image has limits, while with documents or programs you'll see a lot of shrinking.

Just checked Peazip, and found none of such (stupid) lossy compression options. Which is actually better. Less things to worry about.

A tip I always did to ensure future compatibility: make self-extracting archives. They are a bit bigger (a few mb), but will work on their own as well, so if for some reason other (future) programs will refuse to open them you can still access the data.

 

[JoesMorgue]

You are moving the files to an external HD...

Is this drive one that will stay on your computer? I'd recommend taking the HD and storing it, as daily use of the drive will increase the chances of data loss.

 

[Senteaf]

Some compressing programs like say WinRar (that I used before Peazip) did offer me to shrink the images and movies by using lossy compression (that is by decreasing quality). THat's because shrinking the size of a movie or an image has limits, while with documents or programs you'll see a lot of shrinking.

Just checked Peazip, and found none of such (stupid) lossy compression options. Which is actually better. Less things to worry about.

A tip I always did to ensure future compatibility: make self-extracting archives. They are a bit bigger (a few mb), but will work on their own as well, so if for some reason other (future) programs will refuse to open them you can still access the data.

Okay, this is interesting. I did not know WinRAR had such capabilities.
But as far as I know, 7zip and Peazip(from you) don't have. And yes this is stupid really, when huge capacities are cheap nowadays.

Thanks for the tip, I forgot about this option and I will take into consideration.
Or, to add, this program might not work in the future...

You are moving the files to an external HD...

Is this drive one that will stay on your computer? I'd recommend taking the HD and storing it, as daily use of the drive will increase the chances of data loss.

I move files as necessary and then store it back in its case in my living-room.

Now I'd be glad if you could explain why "daily use of the drive will increase the chances of data loss"

 

[JoesMorgue]

A running drive wears.
Every time the drive changes, there is a chance of data loss ever time the "map" get accessed. [A.K.A. FAT, or whatever it is called on NTFS, HFS+, etc]

In use, OR in storage, there is a chance the platter can lose data, that doesn't change.

Storing the drive on a shelf, in an anti-static bag with a anti-moisture pack in it is the safest for long term. I don't know if an anti-static bag would help on an external drive, but it wouldn't hurt.

 

[Senteaf]

So it would be safe to transfer its content to a newly-bought HDD each time?

What is the "map"? maybe you mean the file that lists all files and their bytes and spaces in the HD memory?
probably more which I don't know, I remember vaguely.

 

[JoesMorgue]

So it would be safe to transfer its content to a newly-bought HDD each time?

What is the "map"? maybe you mean the file that lists all files and their bytes and spaces in the HD memory?
probably more which I don't know, I remember vaguely.

In the days of DOS the "Map" was called the FAT. Later it was called the FAT32. I don't know what it is called on a NTFS formated drive.

Here, this will explain more: File Allocation Table - Wikipedia, the free encyclopedia

Transfering it to a new HD every time is a little overboard, but it would work. I just suggested a good method to store files long term...

 

[bobafetthotmail]

well, good backups are always redundant. That is you have at least 2 different memory devices with the same data on them, and you check them regularly to see if they still work and data is still there. This way you cut in half the chance of losing your backup, because if one memory fails, you still have the other. And by checking regularly you notice failures before both devices fail (so you can make a copy before it's too late).

Of course the more memory devices with an additional backup the less the chance of a failure casing data loss, but I don't see the need for more than triple redundancy.

If you can keep the backups in distant places you avoid losing the data in case something big happens and a backup is physically destroyed (fires, droughts, disasters in general).

You can also use cloud storage services, like dropbox or skydrive, as they will handle backups and whatnot for the data you give them.

 

[JoesMorgue]

You can also use cloud storage services, like dropbox or skydrive, as they will handle backups and whatnot for the data you give them.

WHY do I never think of them? Cloud storage is good, but limited [unless your willing to pay] and DropBox syncs with your folder, so a bad file locally would corrupt the DropBox's file.

Then again, I put my archives in the cloud, but every time it rains, I lose data...

 

[Senteaf]

well, good backups are always redundant. That is you have at least 2 different memory devices with the same data on them, and you check them regularly to see if they still work and data is still there. This way you cut in half the chance of losing your backup, because if one memory fails, you still have the other. And by checking regularly you notice failures before both devices fail (so you can make a copy before it's too late).

Of course the more memory devices with an additional backup the less the chance of a failure casing data loss, but I don't see the need for more than triple redundancy.

If you can keep the backups in distant places you avoid losing the data in case something big happens and a backup is physically destroyed (fires, droughts, disasters in general).

You can also use cloud storage services, like dropbox or skydrive, as they will handle backups and whatnot for the data you give them.

hi,
I don't really like cloud storage services, I haven't tried but I don't like the idea its out there. for example family photos from trips and you know...

and I have one memory device with the data i want to backup and I put it in a safe distant place, I only use it for backups.

You can also use cloud storage services, like dropbox or skydrive, as they will handle backups and whatnot for the data you give them.

WHY do I never think of them? Cloud storage is good, but limited [unless your willing to pay] and DropBox syncs with your folder, so a bad file locally would corrupt the DropBox's file.

Then again, I put my archives in the cloud, but every time it rains, I lose data...

yes and it is not as safe as backing up with your own device at your place

And that's a good one with cloud

 

[bobafetthotmail]

I don't really like cloud storage services, I haven't tried but I don't like the idea its out there. for example family photos from trips and you know...

Actually, lockpicking their way to your backup drive and imaging it while you are at work or whatever is significantly easier than hacking a cloud-storage server. But I don't see the reason for some random thief to steal your family pics from either the server or your drive. It's all worthless for someone else, and pedos have far more user-friendly places to farm the underage pics they crave (facebook).

I have nothing so confidential, but your needs may be different.

and I have one memory device with the data i want to backup and I put it in a safe distant place, I only use it for backups.

In case it fails you lost backups. At least 2 devices with the same data is recommended, as hard drives can die without reason, and without warning. (and flash drives aren't that better either for long-term storage)

Not to say that you need to, just that it's much safer to have redundancy.

DropBox syncs with your folder, so a bad file locally would corrupt the DropBox's file.

They keep backups all the way up to 30 days. If you routinely check that newly modified stuff is working before those 30 days you will catch all such "corruptions" (which are kinda rare imho) and revert to the last working version of that file.

 

[JoesMorgue]

What do you [everyone, not just Senteaf] keep your offline backups? How far is far enough away?

 

[bobafetthotmail]

Since fires are not a concern for me (brick house) I have two backups, one close to the computer, one hidden somewhere else. If your house can burn down, then having a backup that will survive the house burning down should be a worthy goal.

Plus 18 GB of free dropbox space for a triple backup for the most important things.

 

[JoesMorgue]

Since fires are not a concern for me (brick house) I have two backups, one close to the computer, one hidden somewhere else. If your house can burn down, then having a backup that will survive the house burning down should be a worthy goal.

Plus 18 GB of free dropbox space for a triple backup for the most important things.

I live just outside Detroit, and I will tell you a brick house can burn down!

 

[bobafetthotmail]

You mean a house with wooden structure and brick exterior (UK-style)?
Seriously, in my house a fire cannot get from a piece of forniture to the other in the same room, go figure melting the bricks of the structural walls.

 

[JoesMorgue]

You mean a house with wooden structure and brick exterior (UK-style)?
Seriously, in my house a fire cannot get from a piece of forniture to the other in the same room, go figure melting the bricks of the structural walls.

Are your floors wood? Rugs? Carpets?



My house is the Brick [faced] one. This pic was taken to capture the tree. An outside fire could catch the roof on fire.

I am NOT accusing you of anything. I'm trying to make you COMPLETELY aware of your environment.