Question about RAID 1

[Theinsidiousgeek]

I plan to make a RAID 1 array. I already have a 4tb WD Green and will be purchasing a 6tb one. I presume when creating a RAID 1 volume with those two drives it will be created as a single 4TB array. But lets say in the future I was to swap the 4tb for a 6tb would I be able to rebuild the Array with the 6TB and then enlarge it to the full 6TB without loosing the data? 

[ShadowCaptain]

I plan to make a RAID 1 array. I already have a 4tb WD Green and will be purchasing a 6tb one. I presume when creating a RAID 1 volume with those two drives it will be created as a single 4TB array. But lets say in the future I was to swap the 4tb for a 6tb would I be able to rebuild the Array with the 6TB and then enlarge it to the full 6TB without loosing the data? 

 

Yes but you will lose the data, I would suggest getting a correct sized drive now instead of fucking around later

[Oshino Shinobu]

Well, if you're swapping the 4TB out for another 6TB, you could transfer all of the data from the array onto the 6TB drive. Break the array, then load all of the data onto the 4TB drive and set up the array with the two 6TB drives, then move the data onto the new array. 

 

I don't think you can just swap out drives and clone the data across. 

 

EDIT: I've read that mixing drives in RAID 1 can seriously mess with performance. It's best to use matched drives. 

[Mighty_Miro_WD]

Hi there@Theinsidiousgeek!

 

You can do RAID 1 with different drives, but the RAID will use the smallest of those two as the main size. Also, like @Oshino Shinobu Shinobi stated, different size drives tend to lead to performance problems.

 

So, it's generally speaking, it can be done if you don't mind sacrificing the extra space on you larger drive to do it.

 

Hope this helps.

 

Cheers!

[unijab]

What you want to do is possible with linux.

 

details:

https://raid.wiki.kernel.org/index.php/Growing

 

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Create partitions to take up the full size on 4 & 6TB drives

Use mdadm to create the raid 1 

 

time passes

 

install additional 6TB drive

partition its full size

fail and remove 4TB drive

add new 6TB drive to array

let resync complete 

after complete, grow it to full size of 6TB drives