I have quite a few DVDs of non-critical archived material - burned in different years, different disc manufacturers, different drives - but certainly some are now about 10 years old.   I've read this question:    about long-term archival media, and I understand there is no silver bullet, but my dilemma has some specific constraints:   I (think I) have to replace my aging DVDs with something I'm willing to spend no more than a few hundred USD, maybe even less. In fact, if I lost this entire archive, I would be annoyed and distraught, but not devastated. The archived material does not become useless if some of it is lost I want to reduce the amount of space my archive takes up; right now my DVDs are in an 'album' of sleeves.   So, I was considering switching to a portable HDD. I'm assuming that I'll replace it every 10 years or so with whatever is available then; but I still fear for the longevity of this choice. With that in mind,   How useful is it to use ZFS with Reed-Solomon codes for storage? Are there other software solutions (not RAID, since we're talking about a single drive, but perhaps RAID between areas of the drive) I could use to increase longevity? Is it a good idea to buy two different portable HDDs and occasionally overwrite one of them with the other? Is the longevity of SSDs higher than that of HDDs when writes are infrequent, as in my case? Should I maybe just get a BluRay recorder and some good-quality discs instead?   To emphasize: I need to make a decision for my own specific scenario.
70063
I have many DVDs with movies and games, they are getting old and dusty, some of them are damaged. And I have more than 300 GB of general files in my PC. I want to store and preserve all of my data and keep them for a long long time.  I want to know what is the best and more reliable storage media that I should use and... I can buy. I will copy all of my DVDs to a new media and throw all of my DVDs away. It will take a very smaller physical space.  I think that everything that I need to store is currently 800 GB.  I do not like optical discs, because they are fragile and I have lost many CDs and DVDs. Hard drives would be good, but they can suddenly stop working, and it is very expensive to recover data from a broken hard drive.  Other questions: How often will I have to copy the files to a new storage media? Is it good idea to have another copy of each file stored in another storage media?  Edit: If I put all of the movies and games in a HDD, if the HDD stops working, I will lose everything. This is how valuable they are for me: If I lose 10% of them, I will not cry, because I can get new ones, but if I lose 90%, it will be a disaster.  Edit 2: I do not think that that online storage is reliable even if I pay for it, because they may be closed or may get bankrupt. They are not from my country and it would be difficult to get the files back.
91446
I'm looking to build a nice little RAID array for dedicated backups. I'd like to have about 2-4TB of space available, as I have this nasty little habit of digitizing everything. Thus, I need a lot of storage and a lot of redundancy in case of drive failure. I'll also essentially be backing up 2-3 computers' /home folders using one of the "Time Machine" clones for Linux. This array will be accessible over my local network via SSH.   I'm having difficulties understanding how RAID-5 achieves parity and how many drives are actually required. One would assume that it needs 5 drives, but I could be wrong. Most of the diagrams I've seen have only yet confused me. It seems that this is how RAID-5 works, please correct me as I'm sure I'm not grasping it properly:  /---STORAGE---\    /---PARITY----\ |   DRIVE_1   |    |   DRIVE_4   | |   DRIVE_2   |----|     ...     | |   DRIVE_3   |    |             | \-------------/    \-------------/   It seems that drives 1-3 appear and work as a single, massive drive (capacity * number_of_drives) and the parity drive(s) back up those drives. What seems strange to me is that I usually see 3+ storage drives in a diagram to only 1 or 2 parity drives. Say we're running 4 1TB drives in a RAID-5 array, 3 running storage and 1 running parity, we have 3TB of actual storage, but only have 1TB of parity!?  I know I'm missing something here, can someone help me out? Also, for my use case, what would be better, RAID-5 or RAID-6? Fault tolerance is the highest priority for me at this point, since it's going to be running over a network for home use only, speed isn't hugely critical.
102095
It is known that after exceeding amount of write procedures to a particular SSD sector this sector dies and is replaced with another one from reserved ones. Please, correct me if I'm wrong.  I suppose it might be unsafe to use SSD disc for very long time. But I would like to know how much damaged is my disc, how many damaged sectors it has? How to get such info? Is there any useful software to check it?
51457
My old laptop has become utterly slow and unresponsive to the extent that after loading it takes a good 30-40 mins before I can even use it. It's mostly in an unresponsive state and doesn't change even if I do a hard restart. I did a SMART test and it shows my hard disk is 58% healthy.   I read somewhere on a forum that the OS or the NTFS disk itself will mark bad sectors and wouldn't write to them. So my question is, my disk is 750 GB, 58% of which is 435GB. My total data on the disk is roughly 300 GB. But I think the hard disk may still be reading/writing to those bad sectors and thus my system is not responsive. So my question is, can I do something in order to block all those bad sectors and use the left over good sectors only ? Most importantly, will it be a good idea in first place or should I just replace the old hard drive?   Note: This is an old computer and I only use it occasionally to stream movies on my tv via hdmi.
11496
I was just reading a question on backups with flash drives, but I was not quite sure why SSDs would be better than flash drives for backups.  To me, solid-state drives look like larger versions of flash drives. But surely there must be something that makes the former much more reliable than the latter.  What's the difference between an SSD and just a regular flash drive? For example, do they both use NAND?
103183
During real, everyday use, that is?  I'm looking to upgrade a drive in a MacBook Pro, and am looking at either a 750GB/7200RPM or a 1TH/5400RPM drive.  Would I care about the speed difference? Is it worth giving up the additional space on the larger drive?
92792
Here's my scenario -- both drives were working perfectly fine. I removed one of the drives for a while (building a new PC, didn't think I was going to use RAID anymore but changed my mind). I actually switch the SATA type to AHCI and was operating for about a week on the new system before deciding to re-enable RAID and reinstall the drive I had removed.   It's currently rebuilding, but I'm curious how it knows which one is the source and which one is out-of-date?
75562
In my job we are not guaranteed to keep using the same computer forever. Also, I need to keep the files at arm's reach when traveling. This is screaming a "cloud" solution, but here in Brazil mobile connectivity is still an issue, and relying on company networks there is always the firewall and network policy issue, so cloud is no-go.  So I started using a 16GB flash drive to store all my personal and work documents. But I am afraid someday the thumb drive will die on me and I will lose everything. Also I have a hard time when I forget it at home and can't access my files.  So I am looking for some utility/script that will run on my home and work computers and whenever I connect the thumb drive, it detects it as my thumb-drive and synchronizes with folders on the computer, kinda like rsync.   These are the needed features:   Securely recognizes the thumb-drive (using a special "key" file or volume serial numbers) Update only modified files (no dumb-copying, as it's several GB) If a file was modified on both on the thumb-drive and the computer, ask for which one to keep. I may choose which folders to sync (do not want to sync the music folder, for example) Non-annoying operation, just ask for a decision on conflicts if needed (but a progress indicator would be nice).   Desirable but not required, are syncing being done automatically before removal (instead of at insertion).  Is there a ready-made Windows tool for this job? This could be pulled out with a batch file but I wanna know if there is something on the market already.  Thanks!  Update for future viewers..  SyncToy is very good, but has the flaw of needing Administrator account for installation. I needed to sync with na old XP work computer, with limited permissions. I've settled for Unison  . It is a command-line app, but matches all my requirements, and does not need  to be installed.
119196
We have a NAS server at the company I work for that is being used for storing photography sessions. Each session is approximately 100gb. Over the last couple of years this server has accumulated 10+ TB of data, and we are increasing the amount of photoshoots exponentially. I estimate that by the end of next year we will have 20+ TB stored on this NAS. We are currently backing this server up to tape using LTO-5 tapes with Symantec BackupExec. Since the size of this server has grown, full backups of this server are not completing overnight. Does anyone have any suggestion on how to backup this amount of data? Should we be backing it up to tape? Are there any other options which may be better?
16122
This is a  about RAID levels.    What are:   the RAID levels typically used (including the RAID-Z family)?  deployments are they commonly found in? benefits and pitfalls of each?
75007
A colleague told me that it is not recommended to use USB hard disks due to the lack of inherent integrity checking of copied files. I am looking for details on that. In what respect is copying to a USB device different from copying to a hard disk connected via e.g. SATA? If anybody has further sources/information on that, I would appreciate sharing it with me.  edit: As explained below, I know that in many cases, the used hard disk is effectively nothing else but a SATA disk in a casing. My question is whether the USB &lt;=> SATA interface introduces data security issues. My colleague referred to a case where a broken USB controller led to data loss. Data could be copied to the hard disk without any problems, but the data written to the disk was corrupted. Replacement of the USB controller resolved the issue in this case.
47103
Yesterday we received some new drives for our in-house fileserver. We ordered 6 12TB HC520 from a supplier and they sent us four which are labeled 4 MAR 2020 and two labeled 18 AUG 2018.  They are meant to be used in a single volume, operating underneath ZFS in a 4:2 configuration (two drives failure protection).  Will the different dates have an affect on the performance or aging of the disks, are the older disks more prone to failure?
119430
It is conventional wisdom¹ that each time you spin a hard disk down and back up, you shave some time off its life expectancy.  The topic has been discussed before:       Common explanations for why spindowns and spinups are harmful are that they induce more stress on the mechanical parts than ordinary running, and that they cause heat variations that are harmful to the device mechanics.  Is there any data showing quantitatively how bad a spin cycle is? That is, how much life expectancy does a spin cycle cost? Or, more practically, if I know that I'm not going to need a disk for X seconds, how large should X be to warrant spinning down?  ¹  But conventional wisdom has been wrong before; for example, it is commonly held that hard disks should be kept as cool as possible, but the  shows that cooler drives actually fail more. This study is no help here since all the disks surveyed were powered on 24/7.
19231
Wife has been using iPhoto/Photos and iMovie for storing family photos and videos for roughly 5 years. Have about a 300 GB iMovie library and 100 GB iPhoto library.  MacBook Pro is getting full (less than 10 GB free) which is obviously beginning to effect performance. Have always used a NAS for Time Machine to back-up but not doing anything offsite.   Not sure what to do to move these libraries or archive them to a) an external HD or b) an offsite storage. Is it possible to just "close" the library and move it to an external HD for archiving. From what I understand in iPhoto/iMovie, if you wanted to access that library later you could simply load that library.   Is there any how-to on this or a better method? Also moving forward should I be keeping the libraries on an external an just accessing them with Photos/iMovie?
100198
My bro used to burn DVD's with some special format to ensure that they would even work on crummy, cheap, old DVD players.  Well, I'm using one of 'those' dvd players.  So, I want to be sure that I format my burned dvd's properly.  What can I do to be sure that my dvd's play properly?  As I recall, we could even use CD disks to on old DVD players, and the CD's would be loaded with .avi files.  I believe the format started with an s and had an h in it.
3238
I'm planning on selling a used external HDD on eBay.  Are there any applications for Mac out there (preferably free) that can show me statistics about the usage history for the drive so that I can let potential buyers know the condition more precisely?
24334
I've run across (personally or by proxy) a bunch of storage media that exhibited physical problems during their life. Hard disks, solid state drives and other flash storage media all fail after some time. The situation is worse with USB flash drives and flash cards because of the large amount of suppliers with inferior flash cell and flash controller quality.  How can I reliably detect if a storage drive suffers from physical damage?  Note that this question isn't about file system integrity (which can be checked with ).