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defcon

Do you still backup if you use duplication?

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Yes, I know there's no substitute for backup, but its not feasible once you get beyond a certain size. And offsite backups would be best but again I don't think its feasible unless you have access to a data center where you can coloc a backup server.

 

So if I enable duplication doesn't that effectively achieve the goal of backups? The other option is to build a 2nd server and use it for backups which is just added expense. I am not worried about accidental deletions, even with a backup server I'd use rsync.

 

What do people use for backup?

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I personally still do back ups to external drives for the most important stuff that I then put in a water and fire proof safe.  Even if you have duplication of the files, this does no good if the entire computer is engulfed in flames.


I use a program called "Allway Sync".  It's a Windows only program and it's a great program.  The best part?  It's "Free for moderate personal use".  But the "Pro" version is only like $25 anyway.

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Duplication <> Backup. And if you are not protected against accidental deletions then it isn't really a backup.

 

Having said this, it is understandable if one does not backup everything as some things are either unimportant or can be regenerated rather easily.

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I use offsite backup, Crashplan. This is purely for disaster recovery, and I did it mostly for my photos and home videos.  Relatively inexpensive and definitely allows me to sleep better.  

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As for the difference between duplication and backup:

 

What happens when you delete the file? 

 

 

Duplication, or any form of redundancy?  It's gone on both locations. 

Backup? Was it backed up? Then you can restore. 

 

Duplication and/or redundnacy is great to prevent loss due to disk failure. But Backup is to preserve the files from other issues, such as deletion, user error, corruption, or .... cryptolocker type stuff. 

 

 

Ideally, you want both. 

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Ideally I'd have everything backed up offsite or offline. But like I said, that needs a 2nd server at least, or managing a bunch of externals and keeping track of which one is filled up when its time to take a backup. Its simply not feasible after a certain size.

 

Most of the time deletion is deliberate - e.g. I delete a movie after I'm done watching. I am willing to live with the dangers of accidental deletion. Actually I think if I use snapraid and have it do a nightly sync/scrub, then it can reconstruct accidentally deleted files because parity is not realtime.

 

But to me the main advantage of duplication is its actually 2 copies of your data which is the most secure form of protection as you don't need any reconstruction. And its effectively a backup since I can resue the disks on other pc's. If it doesn't serve as a kind of backup, then am I gaining much vs a parity solution? After all we are using 2x the disk space.

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Well, a parity solution takes a long time to recover I would think. Some argue that it also puts additional stress on the remaining HDDs, increasing probability of cascading failure (but, IMHO that is quite a stretch). I use duplication solely as a means to increase uptime. Backup for loss due to accidental deletions, viruses, fire, theft etc. And yes, I rotate Server Backups (which include client backups) offsite.

 

What is you setup?

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@Defcon: I completely understand. My datastore is at about that point (with ~50TB of unique data).  Backing it up is ... problematic at best. 

 

As for SnapRAID, that was something I intentionally didn't mention: snapshots.  There are various ways to accomplish this, each have their issues. And as stuff like cryptolocker/ransomware gets more prevalent, it gets smarter (I've read that some variants will dump VSS snapshots immediately, to prevent restore via Previous Versions). 

 

As for redundancy vs parity, there are a lot of arguments that can be made.  Redundancy will always be faster to recover data than parity, because of the added calculations for parity. But redundancy suffers from deletions on both copies. 

 

 

http://community.covecube.com/index.php?/topic/52-faq-parity-and-duplication-and-drivepool/

http://jrs-s.net/2015/02/06/zfs-you-should-use-mirror-vdevs-not-raidz/

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Well, a parity solution takes a long time to recover I would think. Some argue that it also puts additional stress on the remaining HDDs, increasing probability of cascading failure (but, IMHO that is quite a stretch). I use duplication solely as a means to increase uptime. Backup for loss due to accidental deletions, viruses, fire, theft etc. And yes, I rotate Server Backups (which include client backups) offsite.

 

What is you setup?

 

My truly critical data (personal docs etc) is backed up to multiple cloud services and on a usb key I carry with me. For photos right now I have a 1TB Google Drive promo (from buying a chromebook) which is more than enough for all my pics but its going to expire soon.

 

Everything else I manage manually using a bunch of internal + external disks. I have about 80% of my files duplicated, keeping the same folder structure on the main and backup disks, but I have to juggle around files as disks fill up. I think migrating to DrivePool will be easy because I just need to seed, and the balancer should hopefully see I have 2 copies of the same folder structure. I'm not sure How I will tell it to leave the files where they are and not move them around, the file placement/balancer plugin rules look complicated.

 

Drashna, you have a massive server! I'm assuming you are using duplication since it says in your server link that its 117TB, and you mention 50TB data. Do you also do backups and if so how? I've see the discussions on ZFS before, I really don't understand why someone would use it for a home server with so many issues.

 

Ransomware is a scary prospect, I don't know how to prevent that since all files have write access.

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Drashna, you have a massive server! I'm assuming you are using duplication since it says in your server link that its 117TB, and you mention 50TB data. Do you also do backups and if so how? I've see the discussions on ZFS before, I really don't understand why someone would use it for a home server with so many issues.

 

Ransomware is a scary prospect, I don't know how to prevent that since all files have write access.

 

 

Yup, I do. I'm very happy with it... aside from a single REALLY weird issue...

 

The raw storage capacity is 116-117TBs of data.  

 

However, since everything is at least 2x duplicated,  I only have about 50TB of unique data on the pool. (which takes up ~100TBs) 

 

 

As for backups, I don't have any right now.  I know I should, and I do plan on implementing it, but with the data set size .....  I was hoping we would get working ACD support, and use that.  But for now .... that's not happening. 

When we do, or I find a better provider for me .... I'll probably just copy data to a CloudDrive, unmount it, and then periodically update it. 

 

 

 

 

As for ransomware, it's absolutely terrifying.  I've had the "pleasure" of helping a few friends with it, and it's amounted to wiping the systems (before there was the list of keys). 

 

As for limiting stuff... the problem is, the more you limit stuff to prevent this, the harder it is for YOU to access stuff. 

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