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What would happen to hdd and data in case of this raid 5 configuration ?

My  storage server has 12 HDDs.

and  RAID5 group X2

RAID group1 is on the hdd 1 - hdd 7
RAID group2 is on the hdd 8 - hdd12

According to control panel,
for each usage,
hdd 1 is system
hdd 2 is system
hdd 3 is data
hdd 4 is global hot spare
hdd 5 is data
hdd 6 is data
hdd 7 is data

hdd 8 - hdd 12 are data.

My question is  this "system" meaning.
Normally, What do you predict this "system" mean ? RAID5 parity ?
Can global hot spare become alternative hdd instead of the not only failured hdd of RAID5 group1 but  RAID5 group2 ?
If hdd 7 and hdd 6 would be broken at the same time, the data can be recovered automatically after replacment of new hdds ?
what would  happen if hdd 1 and hdd 2 would be broken at the same time ?

Best regards
Server HardwareRAID

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Last Comment

8/22/2022 - Mon
Neil Russell

In a RAID 5 array, the loss of ANY 2 disks would mean a TOTAL loss of the data and the array. You would nee to be paying specialist recovery companies to recover data for you.
Neil Russell

So in answer to your question, if 1 and 2 or 6 and 7 die at the same time, you have lost your entire array. same if 1 and 6 or 3 and 7 or ANY TWO DISKS IN A SINGLE RAID5 ARRAY

A general answer as you have not given the make of the server / raid controllers etc :

You have two raid arrays, 1-7 and 8-12.
As mentioned above if you loose 2 disks in either of these array groups then you would have a fail.
If disks 1 and 6 went bad then that raid group (disks 1 - 7 and everything stored on them would be gone).  the other set - disks 8-12 would carry on working fine.
And the same thing the other way round.

Disks 1,2 are called 'system' and disks 3,5,6 and 7 are called Data.
The likely reason for this is your system is partitioned so you have a first drive for your OS (for example a C drive for windows files) and then the rest of that group is data (maybe D drive for user data) and the other group would be anothe drive again (maybe E:)
This is quite a strange way of doing it.  I wouldhave made those into two seperate raid groups - but then there may have been a reason for it.

Disk 4 is a hot spare.  As long as it has been setup correctly it will become the first failed disk.  So if disk 12 goes wrong, disk 4 will take over.  The data that would have been on disk 12 gets rebuilt off the other disks in its array. After an hour or so the rebuild is finished and you can then look at buying a new disk for the slot 12 disk and making that the new hot spare.

It is unlikely that two disks would go on the same day so this setup should be able to survive a disk fail without even rebooting.

Note - you should also keep tape backups in case this did fail - or in case of corruption or files being deleted by accident etc.
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