I am in the process of putting together my first Linux Server.

I have installed Openmediavault on the following hardware.

MSI B85M-E45
G1850
12 GB RAM (2 x 4GB and 2 x 2GB) -
2 x Samsung F4 2TB HDD
2 x WD Red 6TB HDD
64GB Crucial M4
2 x DVB-T tuner cards
1 x DVB-S2 tuner card
Golden Green HX 350W

The two 2TB Harddrives and one of the 6TB Hardddrives are combined as a single 10TB via mergerfs, with the second 6TB Harddrive acting as a parity drive.

TVHeadend is also installed and does all my recording.

The server acts as a central storage for all my media (recordings, videos, music etc.).

What is the best advice in terms of power saving?

As a general rule, the server is used as follows:

* Between about 6am and 7:30am in the morning, when my son watches TV.

* Between about 6pm (when everyone gets in from school/work) until about 1am, when everyone goes to sleep.

* Randomly throughout the day for recordings (though recordings tend to be in the evening).

Is it better to run the server 24/7 or have it suspend to RAM whenever not in use for, say, 10 mins (and have it automatically wake for recordings)?

What is the best way to deal with spinning down harddrives? Should I do this at all and, if so, after how long?

Any general advice would be much appreciated.

I would probably use solid-state drives nowadays, and I would let it run. It shouldn't consume a significant amount of power.

Thanks - unfortunately, though I would love to replace the mechanical hard drive space with SSDs, they are just way too expensive at the moment.

In the long run it probably does not matter. I'm on the side that believes that cycling often is harder on drives versus leaving them running in regards to temperature, electrical power on surges and Newton's law of motion.

Make sure you can mirror your media to a separate set of drives, or can automatically, intermittently backup in some manner.
Then, make sure you can successfully restore parts of it.

How much space does a days set of recording take?
Perhaps record a days worth to a tmpfs (RAM) and copy in bulk to the HDD all at once to minimze spin up / spin down times?