Greetings. I am very new to Unraid and am about to set up my first Unraid server. I'm wondering about two main things I cannot find answers to:

 

1. My plan is to move media files, shows and movies, from my asustor nas raid 5 volumes and put them on the new unraid server, not in raid 5, instead in unraids parity system. I will leave my personal documents, photos, etc on the asustor nas in raid 5. Would this be advisable over doing the reverse: leaving the asustor nas as the media server and moving personal files (to what i view as less secure, less redundant) unraid parity system.

 

I guess this is a question of performance as well as reliability. My first care is the protection of my personal files and then second concern would be for the rapid delivery of media throughout my home network.

 

2. I understand that the unraid array must have a parity drive for data redundancy. I also understand that that drive needs to be the largest in the array (if they are different sizes). In my case i do have a number of different sized drives. I will start with an 8tb as parity. How many total TBs can the other drives in the array add up to before I need to add more TBs of parity?

 

Related to this parity question is: If i have an 8tb parity drive, another 8tb drive among the data array, can i then later add (one of my freed up drives from current raid5 arrays) that is 4tb as a parity drive?

 

Thanks for your help in advance.

 

GNG

On 2/2/2022 at 7:19 AM, gng said:

My first care is the protection of my personal files and then second concern would be for the rapid delivery of media throughout my home network.

 

You should always have another copy (preferably offline) of any important files.  In your case maybe the ones that really matter should be on both servers if you do not have offline backups?

 

On 2/2/2022 at 7:19 AM, gng said:

2. I understand that the unraid array must have a parity drive for data redundancy. I also understand that that drive needs to be the largest in the array (if they are different sizes). In my case i do have a number of different sized drives. I will start with an 8tb as parity. How many total TBs can the other drives in the array add up to before I need to add more TBs of parity?

The limit is the total of the data drives.   Having said that many people like to use dual parity as the number of drives starts getting larger (e.g. 10  drives) as the chance of a second drive failing while recovering from an initial failed drive start going up.  It is really a user decision on risk/cost benefits.  There are those with a good backup strategy that run without any parity at all.  You might find the discussion of parity in the online documentation that can be accessed via the Manual link at the bottom of the GUI useful.

 

One thing about Unraid is if that the number of simultaneous failed drives exceeds the number of parity drives then you only lose the data on the failed drives unlike traditional RAID systems where you lose the whole array.

 

On 2/2/2022 at 7:19 AM, gng said:

Related to this parity question is: If i have an 8tb parity drive, another 8tb drive among the data array, can i then later add (one of my freed up drives from current raid5 arrays) that is 4tb as a parity drive?

No.  You can add such a drive as a data drive, but none of the parity drives can be smaller than the largest data drive (although they do not have to be the same size).

 

 

Hello @gng and welcome.

You should read a bit on how Unraid parity works here : https://wiki.unraid.net/Manual/Overview#Parity-Protected_Array

And this great video should also help get a better understanding : 

 

I want to thank you folks for your responses. Very helpful and appreciated.