Viewing Second HD on DS218+

[NSquirrel]

I have a DS218+ with two 4Tb HDs mainly accessed by Windows 10, but also iPad and iPhone. Without removing the HDs, is it possible to view the contents of HD 2?

I have set up for RAID 1, so by rights, HD 2 should be a mirror of HD 1, but what if I have not done the setup correctly and HD 2 is not a mirror? Currently I would only find out at the one time I would not want to know (e.g. after a HD 1 problem…)

The Storage Manager shows me both HD 1 and HD 2; it tells me that both have a usable capacity of 3.49T but nothing that shows that there is anything actually stored on HD 2.

Just curious.
TIA

 

[Rusty]

Pictures from Storage Manager?

 

[fredbert]

Storage Pool should detail how the disks are used to create the RAID. Then Volume details volumes and the storage pool being used.

 

[NSquirrel]

Thanks for quick replies. Pictures attached...

 

[Rusty]

This is SHR (Syno version of RAID1). So both drives are in use

 

[NSquirrel]

Thanks Rusty.
Can one actually see the directory listing of HD 2? (OK, it will be the same.)

 

[Rusty]

Thanks Rusty.
Can one actually see the directory listing of HD 2? (OK, it will be the same.)

Both HDDs are a member of a single array, you can't see listing for each drive.

 

[NSquirrel]

OK. Curiosity cured

Thanks, once again, for speedy and helpful replies.

 

[Norseman]

You have me thinking it might not be a bad idea to just get another 4TB drive and simulate HD 1 going down and see how difficult it is to recover data and rebuild the RAID1.

 

[jeyare]

RAID1 rebuild is fast and easy, then speed of the rebuild is limited by:
- your CPU and RAM level (performance and utilization)
- used disk drives (write/read performance)
- used capacity in source disk drive (almost full or just 20%)
- used file capacity structure in source disk drive (lot of small files or large files)
then stop all necessary services used this degraded disk group
perform rebuild
restart the services

 

[NSquirrel]

>> get another 4TB drive and simulate HD 1 going down

For a home use, in RAID 1, I had wondered about using a spare 4TB drive as a quick backup method. E.g. Every few months, take out a drive; put 'spare' back in; erase and rebuild. This leaves the original 4TB as a backup and then becomes the spare a couple of months later. (My reasoning based on brief calculation of estimated time to backup to an external USB3 drive of current 1TB of my 4TB drive. Also, cost wise there is not a great deal of difference between a USB3 external and an internal drive.)

 

[jeyare]

@NSquirrel

Some recommendation to your backup/RAID rebuild operation model:

1. you can purchase USB3/SATA3 adapter, cost from 10Euro (simple version) to 30Euro (include power adapter, proffered)
2. you can use the spare disk for regular (hourly, daily, weekly,...) backup purposes attached to NAS by the USB3/SATA3 adapter
3. when one of your disk drive from SHR will pass away you can put (another) disk drive to rebuild (as you know already)
4. you can still use your backup drive as backup, when sh.t happens during the RAID rebuild and you lose the second disk. You still have the backup drive, what will save your mental health.
RAID is RAID, but backup is backup.
Then cost of the mental health is about new spare disk and the USB3/SATA3 adapter.
What is great for such method - you are not limited by all external disk vendors - what disk is inside the external box. You will chose what kind of disk vendor/line you will use. Reusable for future RAID damage, ...
Simple and useful for home use.
Next added value - you can use this USB3/SATA3 adapter for any SATA disk drive restoration (attached to your computer). Because many times the RAID degradation has been based on a disk repairable damage (home use).

 

[NSquirrel]

Thanks jeyare; good suggestions

 

[jeyare]

you welcome