Optimal RAM amount per TB

[fakokay]

Hi everyone,

I'm new with FreeNAS, running it (v9.3) and loving it. But i'm wondering if my configuration is optimal or could be better. I need a very big storage pool and planning to add some more soon.

My actual setup is :
MotherBoard : http://www.asrockrack.com/general/productdetail.asp?Model=C2550D4I#Specifications
RAM : 16GB DDR3
HDD : 4x8TB (total of 25.5TB - RAID5)

I'm planning to add 4x8TB more soon, that why i'm posting here !

Also :
I'm supprise to see that FreeNAS doesn't show clearly the state (red mean fail, green mean okay, yellow mean warning, etc) for the drives like DROBO does per example... Did i miss something somwehere ? If one drive fail, how can i know where is the failling drive ?

Thx in advance !

 

[Robert Trevellyan]

HDD : 4x8TB (total of 25.5TB - RAID5)

Do you mean RAIDZ1? If so, that's not a good choice with such large drives. If you mean you're using hardware RAID, that's even worse. Either way, you should probably plan to double your RAM, at least.

If one drive fail, how can i know where is the failing drive ?

You need to set up SMART monitoring and email notifications. Then you'll get an email if any of the SMART attributes reaches threshold. Also, set up a SMART testing schedule. Then if a SMART test fails, it will show up in the SMART monitoring and you'll be notified.

 

[fakokay]

Thank for the infos.
- I set my email on the SMART service (was already on but no email).
- Yes i mean RAIDZ1 sorry... Why is it a bad choice for my drives capacity ?

Can i ask what can be the best optimal setup for my needs knowing that i need at least 20TB (and growing in the future) ? And i know, all my datas is already backed up on a simplier NAS since all my datas are for my work (doing video editing), personnal datas, mp3 and some movies.

My evil plan was to stop having several NAS boxes since i want to focus of having one big drive to manage. :)

Regards and thx a lot in advance !

 

[djdwosk97]

Thank for the infos.
- I set my email on the SMART service (was already on but no email).
- Yes i mean RAIDZ1 sorry... Why is it a bad choice for my drives capacity ?

Can i ask what can be the best optimal setup for my needs knowing that i need at least 20TB (and growing in the future) ? And i know, all my datas is already backed up on a simplier NAS since all my datas are for my work (doing video editing), personnal datas, mp3 and some movies.

My evil plan was to stop having several NAS boxes since i want to focus of having one big drive to manage. :)

Regards and thx a lot in advance !

RAIDZ1 is a bad choice due to the likelihood of encountering a URE (Unrecoverable Read Error) when rebuilding the array. Most consumer drives are rated at an URE every 10^14 bytes (about 12TB). So if any one drive fails you'll be rebuilding from 3 8tb drives, which pretty much guarantees you're going to run into a URE and your array will fail to rebuild.

 

[fakokay]

RAIDZ1 is a bad choice due to the likelihood of encountering a URE (Unrecoverable Read Error) when rebuilding the array. Most consumer drives are rated at an URE every 10^14 bytes (about 12TB). So if any one drive fails you'll be rebuilding from 3 8tb drives, which pretty much guarantees you're going to run into a URE and your array will fail to rebuild.

Thx for the reply... Can i ask what can be the best optimal setup for my needs knowing that i need at least 20TB (and growing in the future) ? And i know, all my datas is already backed up on a simplier NAS since all my datas are for my work (doing video editing), personnal datas, mp3 and some movies.

Before building my own nas box, i was using 2 drobo but i didnt like having to manage 2 NAS to manage my datas... That why i was on the impression of building my own will resolve my problem.

I'm starting to think of buying the Synology RS815+ to solve my problem since they already allow 4x8TB in their model, what you guys think ? Knowing that a already do a second backup of my datas anyway.

Cheer !

 

[BigDave]

6TB NAS drives X 6 configured RAIDz2 (single Vdev)
according to this calculator
Usable data space = 21.48 TiB
Future expansion = adding another 6 Drive Vdev (doubling usable capacity)