2-bay NAS with different size disks - possible to mirror just part of the data?

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danchees
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2-bay NAS with different size disks - possible to mirror just part of the data?

Unread post by danchees » Tue Nov 14, 2017 2:19 pm

Ok, maybe title is a bit misleading, but please bear with me as I am completely new to NAS scene (but have advanced system building knowledge).

I am in process of buying my first NAS, primary purpose is media storage, to replace my current setup where streaming box is accessing my desktop's HDDs. But while I am at it, I am looking to get some additional functionality. My usage case then would be to have one large multimedia server and only much smaller section of important stuff that would need redundancy.

Option 1: get a single bay DS118 (not plus, not j) and move entire multimedia library onto it. Should be easy. however, is it also possible to schedule automatic backup of my main PC's documents folder onto DS118 and then again to automatically backup this folder from DS118 to portable drive (that I already own) attached to DS118's USB port. This will make additional backup of important stuff, while not requiring more expensive 2-bay NAS and additional HDD.

option 2: get a dual bay DS218 (vanilla or play) and install one 8TB and one 1TB HDD (my existing one) into it. Use 8TB as backup/share volume just as I would use a single bay NAS. 1TB HDD would show as separate volume. Is it possible to designate some directory from 8TB volume as "important" and mirror only that onto 1TB HDD? Advantage of this would be that both my disks are in same enclosure and I save money on second large HDD. If at any time in the future I decide I want a full mirror, it should be easy to plop another 8TB into the case, but at this point I do not need this.

Thank you very much for any advice!

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HarryPotter
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Re: 2-bay NAS with different size disks - possible to mirror just part of the data?

Unread post by HarryPotter » Tue Nov 14, 2017 8:43 pm

You can backup selected data from one volume to another, but you cant mirror (=SHR1 or RAID1) just part of a disk.
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eaz
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Re: 2-bay NAS with different size disks - possible to mirror just part of the data?

Unread post by eaz » Tue Nov 14, 2017 10:21 pm

as harry potter explains, there is no raid possible with part of a disk.

In addition to scheduled backup (which also gives you versioning), you can easily setup a shared folder sync between one or more shares from one drive to another. It is not a mirror, but it is as close as it gets to get a copy of your data.
I would always recommend to go for a two bay.
Please share if a reply was useful or how the issue was solved, it helps other DS users.

DS415+ (4TB HGST+ 4TB Seagate raid1 + 2*480GB SSD raid1), DS212+ (2*WD red 2TB), previous DS411J, DS106

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Re: 2-bay NAS with different size disks - possible to mirror just part of the data?

Unread post by mervincm » Tue Nov 14, 2017 11:36 pm

Go for the 2 bay. These things last years, what you plan to to with it today may not be the same in 5 years. A little more up front will give you much more flexibility.
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Re: 2-bay NAS with different size disks - possible to mirror just part of the data?

Unread post by HarryPotter » Tue Nov 14, 2017 11:46 pm

eaz wrote:you can easily setup a shared folder sync between one or more shares from one drive to another.
:?: How should this work? Never seen. It syncs between 2 DS, not within the same device.
*Please do not Private Message me for support questions; leave it on the forum so all members can learn. Thanks!*

DS718+ / DSM 6.2-23511 / ST4000VN000-2AH166 / SA400S37120G SSD cache /16 GB RAM
DS415+ / DSM 6.2-23511

LMS 7.9.1-166, 2 Squeezebox 3 + Boom

APC Smart UPS SUA750i

danchees
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Re: 2-bay NAS with different size disks - possible to mirror just part of the data?

Unread post by danchees » Wed Nov 15, 2017 7:38 am

eaz wrote: In addition to scheduled backup (which also gives you versioning), you can easily setup a shared folder sync between one or more shares from one drive to another. It is not a mirror, but it is as close as it gets to get a copy of your data.
Please bear with me just for a bit longer :)

So the setup would be:
- DS218play, one 8Tb HDD, one 1Tb HDD. Separate volumes, no RAID or anything.
- It is then possible to set up (in a non-convoluted way :)) that my documents from desktop PC are automatically backed up to 8Tb HDD in NAS and then again that these documents are backed up (synced) once more to 1Tb HDD *installed in same NAS unit* by copying from 8Tb drive. Yes/No? Thanks in advance!

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Re: 2-bay NAS with different size disks - possible to mirror just part of the data?

Unread post by HarryPotter » Wed Nov 15, 2017 12:26 pm

danchees wrote:these documents are backed up (synced) once more to 1Tb HDD *installed in same NAS unit* by copying from 8Tb drive.
Yes. with HyperBackup this is no problem.
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LMS 7.9.1-166, 2 Squeezebox 3 + Boom

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Re: 2-bay NAS with different size disks - possible to mirror just part of the data?

Unread post by eaz » Wed Nov 15, 2017 7:20 pm

HarryPotter wrote:
eaz wrote:you can easily setup a shared folder sync between one or more shares from one drive to another.
:?: How should this work? Never seen. It syncs between 2 DS, not within the same device.
And again you are 100% right. I think my age is getting hold of my memory, I must have used it to sync between my two DS instead of between two volumes..
Clearly Hyper backup is the way to go here.
Please share if a reply was useful or how the issue was solved, it helps other DS users.

DS415+ (4TB HGST+ 4TB Seagate raid1 + 2*480GB SSD raid1), DS212+ (2*WD red 2TB), previous DS411J, DS106

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