[SOLVED] Terra Master DAS

[PerFrits]

Hi,

Does anyone have experience with the Terra Master D5-300C? - or maybe it's the same for all nas/das devices?

I have installed a RAID 1 on drive 1+2 and that is all fine.
But what happens when it is full?
Do I have to change both or can I just replace one of the drives and format and rebuild a RAID 1?

I do video work and from time to time my clients want me to revisit an old project.
How do I get access to the files on a old RAID 1 Drive if it's no longer installed in the DAS or in an array?

I'm new to the nas/das thing, so I hope my questions makes some kind of sense 😉

Thanks
/Per

 

[13thmonkey]

Many of your problems will go away if you don't use RAID1, but use disk + backup disk instead. Want to expand a drive, go ahead, access files on a disk that isn't in the array, just do it. It would also offer better protection. It still wouldn't be perfect from a protection standpoint, but better than RAID.

RAID is about uptime, can you access data right now if a disk fails, 24x7. If you don't need uptime you don't need raid, if you can afford to wait whilst you access a different disk with the backup on, or run a restore from the backup you don't need raid. You still need a backup with raid.

 

[PerFrits]

Many of your problems will go away if you don't use RAID1, but use disk + backup disk instead. Want to expand a drive, go ahead, access files on a disk that isn't in the array, just do it. It would also offer better protection. It still wouldn't be perfect from a protection standpoint, but better than RAID.

RAID is about uptime, can you access data right now if a disk fails, 24x7. If you don't need uptime you don't need raid, if you can afford to wait whilst you access a different disk with the backup on, or run a restore from the backup you don't need raid. You still need a backup with raid.

Thanks for the input
I had a drive fail on me once and lost a project while working on it. So from that experience I learned that I need a backup working drive. My clients pay maybe $5.000-$6.000 for a film, so it's very important that I keep all the footage safe and have an exact copy of all the files on the drive while working. That's why I choose to go with a RAID 1 since it writes to both drives at the same time. Is there a better way to do that? A typical project is about 1 TB worth of data and I need to work fast.

 

[13thmonkey]

OK, so you do have a special scenario. However if a file gets corrupted during a save on RAID1 then it's corrupted on both, you delete something by accident it's gone on both, ransomware, gone on both etc. etc.

RAID 1 will also be slightly slower..

Consider your workflow, first off keep a copy of the source files elsewhere (I expect this is teaching you suck eggs). At each stage in the process make a backup, so that if you have a disk fail you've only lost the latest stage, ideally maybe 2 hrs of work that kind of level, so with a long day you can recover your position. (there is some software that will constantly scan and backup a drive, BUT will also allow historic views of documents, so if there was a corruption issue you could go back to the last image of that file)

It's a balance between the of a drive failure that you then might spend a few hours recovering from and how often that might happen, vs the risk of something else happening that you can't recover from. Personally i'd take the risk of a few hours of work over an unrecoverable situation.

Or raid1 and a backup, but that needs more disk slots.

To expand raid 1 you need to (depending on the precise implementation) remove all of the data, replace disks, build the array, replace the data.

Consider storage spaces, you 'thin provision' them so using 2x4TB disks you can create a mirrored 16TB logical drive, that you add pairs of disks to when you need to.