[CentOS] info about hdds in raid

Eugeneapolinary Ju wrote:
> How can I tell wich HDD to swap, when the "cat /proc/mdstat" says one 
> HDD of the RAID1 array has died?
>
> Does the HDD's has some serial numbers, that I can see in "reality", 
> and I can get that number from e.g.: a commands output?
>
> How could I know wich HDD to swap in e.g.: a RAID1 array?
>
> thank you
>
>
# smartctl -a /dev/sda
and so on
This will give you the serial # of the working drives.
You'll then have to power down and search for the one not in your 
serial# list.
Make sure to have a good backup first.