Home NAS servers are one of the most popular devices to create a private cloud in our home, storing all files and folders locally, and without the need to use public cloud storage services, such as Dropbox, Google Drive or similar . Knowing how much storage space we need in a NAS, before buying hard drives, is essential so as not to fall “short” of storage later. Next, we are going to explain everything you need to know about how much space you will need on your NAS.
Space for domestic use
If you are thinking of buying a NAS server for home use, depending on what you are going to store on it, you will need more or less storage space. Next, we are going to indicate all the uses of your NAS that consume a greater amount of storage space:
- Using Plex Media Server to play media content: This is the most storage-intensive usage on a NAS. Depending on the movies and series you have, their resolution (1080p or 4K) and also their bitrate, each movie can occupy approximately 30GB.
- Photo and video storage: Home photos and videos also tend to take up a lot of space. Over the years, we store more and more photos, and possibly more videos, which are of increasingly higher quality, so they take up a lot of space.
- Virtual machines: if you are going to use virtual machines, especially Windows, you are going to need about 100GB for each virtual machine, so you need to adequately size the total storage space.
If you are going to use the NAS in a basic way for photos and videos, and multimedia content sporadically, we believe that 3TB of effective storage is enough. If you are going to add the use of Plex Media Server with a lot of movies, then this is likely to be quite short, and you will have to go to about 5TB of effective storage. Finally, if you are also going to virtualize operating systems on your NAS and you are going to use the space reserved for snapshots, you will have to go to approximately 7TB of effective capacity.
The effective capacity we refer to the storage space that can actually be used, because then we have to take into account that the capacity indicated by the manufacturers of hard drives is measured in GiB (1000GB is 1TB) instead of GB (1024GB is 1TB). ), so when we have large hard drives, the loss due to this is quite significant. In addition, we must also take into account the space that is wasted by the file system used and even the operating system of the NAS, since it is saved on the disk. For example, of a 6TB hard drive, the effective capacity is really around 5.6TB, so we must take this into account.
In the following image you can see hard drives with a capacity of 10TB according to the manufacturer, and that we are using a RAID 5, so the effective capacity is about 26TB.
Other very important aspects to know how much space you will need is that we can reserve some available disk space for snapshots, as long as the operating system supports it. This means that we could have 20% of the storage space dedicated exclusively to snapshots, which is normal, although we can lower it to 10%. If we have a storage capacity of 4TB, 20% is about 800GB, so we must carefully choose the capacity of the hard drives to use.
Drive bays and RAID type
Once we have defined the use of a server and the difference between gross storage space and effective storage space, we must take into account the number of bays that our NAS server has and also the type of RAID that we have. If we have a NAS with two storage bays, our recommendation is that you buy larger hard drives than necessary, because later you will not be able to expand it, but you will have to replace both drives with others of greater capacity, so the expense it will be quite high.
You must bear in mind that if you use RAID 1 or RAID 5, which is the most common in a domestic environment, in the first case you will lose half of the effective storage space, that is, two 4TB hard drives will really have about 3 .8TB (effective) for storage, as one of the hard drives is used as a “mirror” to protect our data against catastrophic drive failure. In the case of RAID 5, we will only lose the storage space corresponding to one of the disks since it is used for parity, for example, if we have 3 4TB hard disks, the effective storage space is approximately 7.8TB.
It is very important to choose the type of RAID that is right for our needs, and also to buy hard drives with more capacity than we initially need, in order not to fall short.
