How do you know if RAID1 works?

I’d like to know what i have saved on my disc1 and to check what is on my disc2…
How can i do that ?
Thanks to all.

You cannot check by yourself easily. You have to trust the MDADM software RAID in Linux. But if you have RAID 1 running, the Linux will take care about all and will inform you immediately if something is not well.

Thanks a lot for your answer.
But do you know a way to see the capacity of each disc (that will be the minimum check :smile:).

RAID 1 aka Mirror Mode will use both disks in a so called array. The capacity in use is 50% of this array as the “second” disc will be used for keeping data of the “first” disk indentical.

Let’s say, it’s a My Cloud Mirror 4 TB, then the capacity in use is 2 TB.
Please note that the capacity values are calculated in decimal not binary, so teh capcity in use shown by Windows for expample is lower than 2 TB.

Hello again Joerg,
Sorry because my question wasn’t clear enough (i’m french).
I’d like to check the free or used capacity on each 2 disks after a new save so i’ll be a little check…
Thanks if you know.
And thanks a lot to respond to me.

Bonjour Marc

the capacity in use and free is shown on the dashbord of the My Cloud web interface. That’s all you can see.

Thanks Joerg,
So you can only check le disc1…
What a pity !!
Thanks again.

not exactly…

the system always checks both disc 1 and 2 but what you see as capacity values is the RAID 1.
Don’t mix “discs” and “RAID” here.

The internal discs are checked by and under control of the the Linux system.
The “capacity” is the result of the RAID system which is running one level above the disc level.