How to Replace Drives for Newbies

[S0L0]

I am planning on building my own Nas with Freenas 9.x using a 4 bay chassis, at the moment I have four ST2000DM001 drives. However over time I'd like to upgrade to four 4TB drives for a total of 16TB, I know this is possible from reading the FAQ section however I haven't being able to find any how to guides on how to replace a drive. I am planning on going with the general rule of thumb of 1GB RAM/1TB using 16GB of RAM for my build but I am bit confused about whether this rule applies to mirrored data or not? For example if I am only using two of the drives for actual storage and having the other two mirror the data would I still need 16GB of RAM for the 16TB of storage?

 

[Dusan]

Did you check the documentation?: http://doc.freenas.org/index.php/Volumes#Replacing_Drives_to_Grow_a_ZFS_Pool
The memory thumbrule calculates with pool capacity, not capacity of the drives. So, in your case 8GB should be OK.

 

[cyberjock]

How to replace a drive is clearly documented in the manual and wiki page.

 

[S0L0]

Did you check the documentation?: http://doc.freenas.org/index.php/Volumes#Replacing_Drives_to_Grow_a_ZFS_Pool
The memory thumbrule calculates with pool capacity, not capacity of the drives. So, in your case 8GB should be OK.

Thanks for the link Dusan, and just to be clear, if I were to have 32 tb and mirroed half of it than in that case I would need 16 gb of ram to manage the pool capacity of 16tb?

 

[S0L0]

Would there be any noticeable increase in performance to having 16gb of ram for an 8tb pool?