New NAS question

kamikazi · January 20, 2015

I am building a new NAS for my home going to be used for network storage and movie playback through plex. Planned 16tb of total storage when project is complete, 8 2tb HDDs. Planned raid 5 array. I was wondering for an array and storage solution like this. Is it necessary to run a dedicated raid card or can I get a board with built in raid with enough ports and be ok?

Thank you ahead of time.

soaringchicken · January 20, 2015

You should be fine with in-built raid :3

MrBucket101 · January 20, 2015

@kamikazi

STAY AWAY FROM ONBOARD RAID. Generally speaking. It has the worst parts of hardware and software raid. Many will agree that hardware raid = software raid, but you will be hard pressed to find anyone who recommends onboard fakeRAID solutions over hardware/software raid. There are some exceptions to this, with some server class motherboards having onboard LSI controllers and what not, but most motherboards employ fakeRAID.

Having used hardware/software raid, I prefer hardware raid, but it's all preference really. Software raid has come a long way since it first started.

Software raid is cheaper, and offers more flexability. Hardware RAID is more expensive, but lets you offload the calculations from the CPU, and also lets you enable some more advanced performance and optimization features.

Look at the 10TB+ Storage thread and see what kind of RAID most of the list is using.

ZFS if it's ever completed 100% will be superior, but it requires 1GB ECC RAM per TB (ECC RAM isn't cheap). There are users on the forum who use ZFS, but it's still actively being developed, and they recommend always running the latest/greatest build to reduce chances of data loss. This is where preference comes in, I don't want to put my precious data on the bleeding edge. I have used mdadm to manage a small 6TB RAID 5 array of 1TB drives, and I liked how I could migrate the array independent of hardware. I even mailed the disks to a friend with the commands to auto-mount the array from the disks.

One last thing, RAID 5 is not recommended at capacities greater than or equal to 12TB. This is due to the increased sector count and the chance of a bad sector existing on another drive, after a single drive has failed. The bad sector can prevent a successful rebuild. RAID 6 mitigates this problem by adding a second parity drive. I highly consider you look into RAID 6 over RAID 5