synology ds218


New member
Aug 15, 2022
hi i was woundering if i could have some advice about this drive , it has got 2 x 4tb drives installed which are on raid 1 that now shows both are 3.6 tb
now when i am finished copying files eg new movies it shows 2.83 tb now when i create another folder eg movie collection it shows 2.83tb but there is nothing on it , so unsure why its showing the drive is used when its empty
any ideas thanks
Hi @gizmo, welcome to Computer Forums!

I expect the reason both drives are showing data in use would be having them set in RAID1. In RAID1, they act as a single hard drive, with the second drive mirroring the contents of the first.

The advantage to this is if one drive fails, the other will have a copy of the files.

If you’re not that concerned about losing what you’re storing eg films that can be downloaded again, your best bet would be to set them up in RAID0. In this mode, the drives will be combined, so you should end up with close to 8TB if you have 4TB drives (you never quite get the full capacity unfortunately, when I had a 8TB NAS I got around 7.3TB of free space)

You should find that you get close to your drive capacity with RAID0 as there is no parity overhead.
HI many thanks for your reply it sounds like i dont have big enough hard drives as i would like protection is it possible to have different size drives and intall pool onto the smaller drive ? all my movies etc are on external 5tb drive and now trying to put them on a nas thanks for your advice
As your NAS is a 2-bay device, the only two ways you can improve your storage would be either to fit new higher capacity drives it set to RAID0 to "combine" the drives at the expense of maintaining 2 copies of the data.

My personal choice in this situation would be to switch to RAID0, and take a seperate backup of the most important files (RAID is not a backup so maintaining a seperate copy is generally a good idea!)
many thanks for your advice at the moment i am thinking about a 4 bay nas as cheap as possible i thought it would have been lots of space using 2 x 4tb drive but with the understanding now that it makes 2 copys at once . i would like to keep protection incase of drive hd issues , i have been trying to learn from youtube but no nothing about port forwarding on a router so at the moment i am using the in built firewall of dsm .. thanks
Depending on if you can afford the power these days I’d say your best bet is an old (server) PC and a copy of Unraid. There’s a fair learning curve if you want to get really fancy with things but for a basic file store it’ll work well. You can add drives as you go and you can buy hardware fairly cheap second hand.

In terms of port forwarding this is something only relevant if you want to access what you’ve got stored when you are outside your home. If you just want to watch videos or access files when you’re home it’s best to not forward any ports and keep things behind your routers firewall.
many thanks for your advice we have got a old pc but unsure what it has in it , we went from pc to nas due to space
i had a look on youtube about unraid looks intersting but unsure if old pc would work out ?
so if i went from nas to pc server what would be the point of the nas if you put your files onto pc server ?
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