I’ve recently started using SkyDrive and DropBox for files that I need to access from multiple locations. (I used to just email them to myself but this has gotten unwieldy.) If it’s important of course I keep a local copy as well but I’m curious as to how secure these kinds of services are against loss of data. Can a single physical event happening to a single hard drive somewhere wipe out my files? Or are there multiple copies, either in the sense that they are backed up, or in the sense that there are just multiple copies on multiple servers available?
Most of the bigger cloud storage companies offer “version history”, a feature that lets you restore old versions of files or undelete files you deleted on your local computers. Usually it’s an extra charge or only available in their more expensive plans.
Here’s Dropbox’s version, for example: What Happens When I Delete files in Dropbox? - Dropbox Help
So that seems like a nice safeguard against your own mistakes.
As for the storage provider losing data themselves, I haven’t heard of any major cases of that happening, but I don’t follow the industry all that closely. Any sane data storage company will have redundant storage across the world (or at least across one country), but depending on how important your data is to you you can probably negotiate different levels of redundancy with them. Amazon’s web services, for example, have gone done a few times with major outages, but never all across the world at the same time. And I don’t think there was data loss from those incidents, just connectivity losses.
You should read up on the MegaUpload case. It wasn’t just illegally copied data that was a copyright violation that was seized.
That particular problem would be less likely to occur for DropBox, but the point is, it’s not just physical failure that can cause you to lose access to your data.
Likely not. For most large scale data centres, there are enough hard drives that hardware failures are inevitable. Large scale file systems like GFS have replication built in internally, so that replicas of each chunk are kept on independent drives, and on independent racks. This isn’t just for redundancy – the additional copies can speed up read rates as well.
I only keep stuff in my dropbox that is inconsequential, spreadsheets for cap ship building and planetary interaction for EVE Online, copies of recipes that I might want to access anywhere, a copy of my medical records as a backup to the medicalert/USB bracelet I have, and a copy of my email address book done in a substitution code. Nothing that would really bother me to be cracked by the NSA, or lead to being able to decode my scheme for making passwords.
Hell, the NSA probably have already browsed it and cracked my address book, and are sitting there nomming my cardamon-lingonberry thumbprint cookies and laughing at this thread while the lions-head meatball soup is simmering in the break room on a hot plate…
This is one of those things, like security, where you don’t know how reliable it is until something goes wrong. That said, I’ve seen Google Drive (actually Picasa Web Albums) go down for about an hour once every few months, but no data loss.
With Dropbox, unless you’re doing it wrong, you’ll have your data in more than one place. I have my Dropbox account synced to my desktop at work, my desktop at home, and a laptop I carry. All three of these plus all of Dropbox’s servers would have to go out at once for me to lose my data.
Dropbox uses Amazon’s S3 service for storage, and Amazon says “the service redundantly stores data in multiple facilities and on multiple devices within each facility. To increase durability, Amazon S3 synchronously stores your data across multiple facilities.”
Dropbox stores the files locally on your PC, so they are accessible even, if you do not have internet access.
The important thing to remember with it is, that if you delete your local files, that they will be deleted the next time that computer goes online on every other computer.
This is what happened to one of my customer, he was running out of space on one of his older PC’s and started deleting the local files in dropbox and then panicked, when the files disappeared on his other PC’s & Laptops.
He thought that they will be safe in the cloud.
When he panic-stricken phoned me, he even told me, that the files are there and when he goes online with that PC the files disappear in front of him. Gladly there was ONE computer containing the files that has not been turned on that day, due to the secretary being sick and it saved/contained their 125GB of files. These files were locally copied and then uploaded into the dropbox folders again.
That was unnecessary. If the files were just recently deleted, you can go to the dropbox website and restore them from there, even if all the local mirrors have them deleted.
Megaupload, IIRC, was renting their servers from various locations around the world. Using their 500-pound-gorilla tactics, the US effectively seized all Kim Dotcom’s assets, so he could not pay the rental on the servers. The owners of those servers were not about to make the decision to turn them back on while the USA was claiming they were violating US law by offering some of the files for download. Besides, without the authentication servers the data was more complicated to access anyway… Not a trivial problem.
After repeated warnings the server farms wiped his data and reused the servers to avoid losing any more revenue.
So it’s not just where and how many copies, it’s also “does the company own the equipment itself” or are they just leasing space? Also, are their services totally legit or are they being taken advantage of in a way that would invite legal scrutiny?
…not 2 days later after syncing your PC you deleted your files several times over the weekend with dropbox.
SkyDrive can be configured to do this too, the option is called “make available offline” and available when you right-click on a folder. You can set this for individual folders or your entire SkyDrive folder.
Also, your local Dropbox folder is just a regular folder on your computer that Dropbox monitors and synchronizes to the online account. Same with SkyDrive, if you select the “make available offline” option. So you can back up these folders the same way you back up any folder. They are part of the Users<username> folder, so if you are backing up that entire folder, you are already backing up your online files.
And if you are using the File History feature on Windows-8, it should already be including the SkyDrive folder. If you’re on Win7, this article says you can enable the “Previous Versions” feature for SKyDrive.
His files were gone (even online) – I don’t know what he’s done with it.
I’m aware of Packrat, but it’s only available with Pro and even then it looks like you need to enable it.
It may be too late now, but you have to click on the trashcan button to show deleted files. It will change to have an open lid. Deleted files will then appear in grey with “deleted file” as filetype. Then you can right-click on it an select “restore”.
It’s not really very intuitive, as it looks to me like a button to delete files, not restore them.
Defiantly to late at this stage.
This trashcan thingy is available in the free version as well.
It’s impossible to say how secure they are. If one of us was an engineer at one of those places we could give a better answer as to how the back-end works, but even then there can be and have been show-stopping bugs that have lost data in numerous computer systems over the years. A more likely bug scenario is temporary data loss until it is restored from backup, or a breakdown in the retrieval system for a period of time. Either way if you needed your cloud data during the outage, tough luck for you. The only thing you can really trust is yourself.
Don’t trust yourself, either.