DS920+ expansion alternative

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DS920+ expansion alternative

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Hi everyone,
I'm looking for expansion unit - for backup purposes only. yes for the same location of where my nas is.
Currently I'm using 1-bay USB enclosure and backup my NAS. lots of cable and these disks are quite old and I don't trust them anymore so I'm looking for a replacement with more elegent solution.

My goal is just to have a cold backup which is offline unless I manually turn it on and that I can quickly take spin the drive without too much vibration / connecting and basically handling disks with my hands.
I found a very attractive price for WD My book Duo that has USB-C. it has RAID0, 1 and JBOD.
in case I configure it as JBOD, will Synology NAS recognize two drives connected with the USB??

will Synology NAS recognize two drives connected with the USB
In general yes. Any enclosure that can manage its own raid array and then present that array as a single "large drive", should work just fine on your Synology.

I thought at 1st you are looking for the official Synology RX units, but I guess this is not the case.
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Thanks. What about JBOD mode, will it works?

specifically I’m want to buy My Book Duo which is currently at a very attractive price.
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Thanks. What about JBOD mode, will it works?

specifically I’m want to buy My Book Duo which is currently at a very attractive price.
Again, as long as that jbod config is managed on the my book duo, syno should see the volume just fine using the compatible file format.
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I found a very attractive price for WD My book Duo
How good is that vs a similar TB-sized WD Elements? This single disk product now spans 2 to 18TB. Doesn't have USB-C.

I've used WD My Book in the past, started with their 'Mac' variants that had Firewire interfaces. They worked well but...but...but... the My Book includes the Hardware Encryption and Password Protection 'feature'. What this means is that even when you don't use it (no password is set) the enclosure's interface card still encrypts (or otherwise obscures) the the whole disk such that only that enclosure can be used to access the data. If that enclosure fails then your data cannot be recovered, at best you can move it to a new enclosure, reformat the disk, and start again.

The simple WD Elements don't have the encryption feature and the disks can be swapped out to another enclosure (not a My Book), whether another Elements or other empty one.

My preference would be to use as simple an enclosure as possible or use another network device that can be used to store the backup off the NAS. Your offline-when-not-backing-up approach is similar to the logical separation that another NAS/rsync server would provide.
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Wow! so the single point of failure which is the enclosure, can basically ruin the whole backup!
Is there any way to bypass it?
What if you set a password? would that password allow you to decrypt the data? See below link:
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I got a discount from work which take the My Book Duo 4TB down to £60. It's also meet my requirement so why not?

- Main question is if I set it at JBOD, would DS920+ recognise 2 x HDD?
- Second question (thanks @fredbert) if it possible to decrypt the disks. I could find some long procedure but also read that DiskGenius can help. with password or without, that's already another question :)
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OK, £60 makes more sense. I see the 4TB WD Elements is currently £82.

The unit's USB interface should present as a normal storage device regardless how it internally manages the hardware, whether RAID or JBOD.

I just steer clear of the My Book and get simple Elements. If there is a way to recover then that's up to people if they want to do it. If I'm using a My Book (only 1 remaining) or Elements as a working disk then I also fully back it up. There were a lot of posts on the WD forum thread where is seemed people didn't backup their data.

Using a UPS for my Macs, external devices, and NASs has really minimised failures.
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Thanks. I have a good setup of backup and archiving, I’m no concerned about that.
All I wanted to make sure is that JBOD box 2-bay would be recognised as 2 disks on Synology NAS. It’s not 100% clear yet from what everyone replying- although I do appreciate your help a lot! Perhaps I wasn’t clear

I do understand that Mybook or any USB drive can be recognised (in general) - I also have these products. Elements, passport etc.
I also understand that My Book Duo with RAID enabled will be recognised as 1 drive

but again, can someone please clarify if JBOD 2 bay box like WD my book duo, can be recognised as 2 separate disks in Synology?
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but again, can someone please clarify if JBOD 2 bay box like WD my book duo, can be recognised as 2 separate disks in Synology?
That intention completely escaped me. I thought you asked about using JBOD on the two drives together and the unified storage being recognised as a single volume via USB.

Does the My Book Duo actually support having the two drives presented separately via the single USB? If it does then there'd be no JBOD involved. The little I read seemed to imply that the WD Mac/PC software would allow the two drives to be configured together as a single RAID 0, RAID 1, or JBOD.

Can't help any more, if I did at all, may be someone else can add something.
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Thanks. I guess it’s my mistake then.
I thought that JBOD in 2 bay means simply 2 drives.

sorry, it’s my misunderstanding, I’m still learning about storage.
Would that be the case for any expansion? (Qnap, synology expansion) that all bays presented as single drive?
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Don't know about QNAP but the Synology DX517 expansion unit is the one that the DS720+ would use. This unit allows the extra bays to be configured as if they are internal to the DS720+, though it's best not to span an array across main and expansion units. What this means is that the expansion unit bays can used to create any storage type that is supported by the main unit (Basic, SHR-1/2, RAID 0/1/5/6: see the spec sheet for full deets).

But the DX517 is around the same price as a DS420+ so not cheap, and why the general response is to get the right sized main unit instead of thinking you'll add DX later. Also, instead of thinking about an expansion unit for holding backups, for this money, you should think about a second NAS or similar.

Having off-NAS backups will isolate the backup data from any risk of malware going rampant on the main unit (inc. expansion). You could use a j-series NAS for purely backup (they support ext4 file system) or if you want btrfs for snapshot/replication then a DS218/418 is the cheapest. This would be far away from the £60 of the My Book Duo.

As I said originally, I'm simple and like simple solutions which is why I'd err on the WD Elements 4TB. Yes it's £20 more (or 33%) but it just works. Having said that I think I saw the My Book Duo includes two WD Red drives and the Elements will most likely be a WD Blue... would that make a difference to you? For backup I still use a mix of WD Blue, Green (old), and whatever they use for white label 12TB.

Maybe a use case for My Book Duo is for faster, direct storage on the Mac using RAID 0: which has better throughput than either RAID 1 or JBOD. But still needs to be backed up.

It's difficult to tell someone what to do because everyone has different needs and subjective relationship with risk.
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I already have another NAS setup and syncing data. I totally agree that Synology expansion unit is NOT attractive at all. Maybe from power consumption point of view.

The setup I have for example is:
DS920+ syncing with another remote NAS (non-syno)
Cold backup on HGST 2.5', Seagate 3.5' and WD SSD done manually - sometimes I backup to additional WD Passport Ultra (yes I'm happy with manually and I know that I'm paranoid)
-- What I wanted is an affordable fast standby backup of non-network device that will connect to the eSATA/USB and remain on/standby. that's why I do like the WD My Book Duo or QNAP expansions. not choosing QNAP because of the £60 price point for My book Duo. @fredbert thanks for letting me know about the encryption! I had no idea and i learnt something super important. in my case, £60 is too attractive so I'll take the risk. This device is just an extra safety net

I thought JBOD means separate disks and identified as separate from the NAS, because I wanted to use Rsync between them rather than RAID1.
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in my case, £60 is too attractive so I'll take the risk. This device is just an extra safety net
I'd be tempted, if for no other reason than to learn. If it doesn't work out then I'd think about reformat and use it with the Mac as direct attached storage. USB 3 is just about bearable to make bootable clones of macOS on HDD.
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And since you've mentioned macOS I have another question :)
If I understand correctly, My Book Duo can only be reformatted to NTFS or HFS+ which Synology should be ok with.
Is there an option (or motive) to reformat to EXT4?
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To use with macOS I'd format it as HFS+. Haven't tried NTFS with Mac, or not recently as it used to (still?) require a third-party file system extension.

If DSM's Control Panel can work with the MDDuo then it would be the way to reformat to ext4. I format to ext4 if the external drive is to be 100% used with NAS, such as for HB data. If I'm going to swap it between other devices then HFS+ or exFAT, depends on devices.
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NTFS supported on macOS with a 3rd party. I thought maybe NTFS/EXT4 is the format to go with simply because there is a way to decrypt MyBookDuo with windows/Linux.
exFAT idea is great but two things bothering me.
1. Synology would let me buy the exFAT license - only if I register to their account. One of the reasons for me using the NAS is because I don't want to be dependent on any vendor! I'm happy to pay the exFAT fee, but don't want to use any vendor/online account.
2. exFAT doesn't have a journal - that said, I'm saying it even though I'm stupid at storage topic! maybe I'm completely wrong and exFAT for the use case above is great and not having journal is not going to impact.
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Sounds like the exFAT package will become free sometime in the future (where did I read that? re DSM 7? was a couple of days ago). That'll be too late even if it does happen.

Check if WD supply the NTFS extension for macOS. A couple of years ago I looked at the Seagate Backup equivalent, not realising it wasn't a simple USB drive, and I think it included NTFS for Mac. Otherwise there's Paragon for buying it (£16 + vat).

You probably should wait and test out what works with the NAS and Mac then decide on the final file system. I'd see how the different file systems handle filenames differently and how they get mangled when copied between to/from the MDDuo ... Mac can handle many more symbols in filenames than Windows. You may find that there's a clear winner once you've tried working with it.
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Microsoft released the license since the integration with Linux kernel, but for some reason, Synology continues to charge illegally for exFat! It’s under GPLv2 now!!
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