Corrupted files NAS Mirror etc.

[Jay226]

Simple question. I was considering making a FreeNas box to insure the stability of my data long term. All I'm trying to preserve is my photos, videos and financial files, as these files cannot be replaced. Looking at FreeNas and ZFS it seems like a solid idea. But I question my logic in the fact that I have data from over 10 years ago and I have never seen a corrupted file. I've read so many posts about the use of ECC and it makes sense, but I say to myself, when have I ever seen corruption in my files. I primary do offsite backups with an external hard drive. I have some of the data backed up on DVD and will move to Blurays soon, as a secondary media. I'm not saying this couldn't happen, but if you read about ECC and single bit errors.... which I haven't used ECC in the last 15 years.... my data should of been trashed along time ago.

 

what am I missing?

 

Thanks guys.

[IdeaStormer]

So you think you can prove a photo image file has all its bits exactly as they were on day one? Or just that you can't see any difference? Just because you can open the file and view it does not mean its not corrupt or degraded.

 

Too bad you didn't do checksums on all your files on day one, then we'd have some solid data.

[Jay226]

One thing I wonder is if data corruption occur more when files are being accessed more often in a large server verse a home backup server where the data resides for long periods of time never being opened, accessed and stored in memory. Any truth to that statement?

[IdeaStormer]

Data corruption occurs when bits flip or are not readable or are read wrong, all the probability to validating if a bit is 0 or 1 in a transistor are what go into causing data corruption, there are papers and papers on the subject, then all the transistors that it takes to actually process a read factor in. Then there's the failure modes that can lead to corrupted data. This is why ECC Memory (RAM) exists and filesystems that try to prevent it from happening by adding safety measures (ZFS and the like).