Raid Levels

[Skevans]

I have just built a NAS and it will be running freeNas. i have 4 3Tb WD reds. The main use for this nas is to act as a media server it will be running plex, and also act as your typical data backup. What Raid level would anyone recommend for this build. I currently have about 3Tb of media. I would prefer not to lose half my storage to redundancy, but if that is the concuss for best option i can live with it.

[KirbyTech]

For that number of drives a RAID 5 would be your best bet. 

[Wylly]

If I'm not mistaken, freenas only uses ZFS, so RAIDZ1 or RAIDZ2 would be.

[beavo451]

Disable any and all hardware RAID. Create a pool using RAIDZ1 from within FreeNAS.

[dalekphalm]

2 hours ago, Skevans said:

I have just built a NAS and it will be running freeNas. i have 4 3Tb WD reds. The main use for this nas is to act as a media server it will be running plex, and also act as your typical data backup. What Raid level would anyone recommend for this build. I currently have about 3Tb of media. I would prefer not to lose half my storage to redundancy, but if that is the concuss for best option i can live with it.

 

43 minutes ago, Wylly said:

If I'm not mistaken, freenas only uses ZFS, so RAIDZ1 or RAIDZ2 would be.

You also have a ZFS "RAID1"-comparable array as well. It's a mirrored vdev I believe.

4 minutes ago, beavo451 said:

Disable any and all hardware RAID. Create a pool using RAIDZ1 from within FreeNAS.

I think it's already implied that he will be using RAIDZ, but it is good to explicitly state it.

 

@Skevans I would suggest either a RAIDZ (RAID5 equivalent) or a Mirrored vdev (RAID1 equivalent).

 

RAIDZ1 (RAID5) would be fine, as long as any important data has at least two copies (One on your NAS, and one elsewhere, eg, a Backup for the NAS, or cloud storage, or on your actual PC). The problem with RAID5 (Less of an issue with RAIDZ) is that when you have a drive failure, and you go to rebuild the drives, you have a decent chance that one of the other drives will have an unrecoverable error during rebuild. In a normal RAID5 environment, this would simply toast the array, and you'd lose all data. In ZFS RAIDZ, you would simply lose that one file contained within the unrecoverable error, and the rest of your array would survive.

 

Having a mirrored vdev RAID1 equivalent would give you better data redundancy, allowing up to two drives to fail.

 

In your case, RAIDZ (RAID5) is probably fine.