UGREEN NAS Storage: UGOS Pro, 16GB Reserve, and Usable Capacity
UGREEN has not published a system reserve figure for UGOS Pro that we can cite, so the RAID calculator gives UGREEN the layout maths only: the space each RAID level leaves from your drives, before UGOS Pro's own system and file system overhead.
See exactly how much usable storage your configuration delivers.
What the calculator does for UGREEN
Choose UGREEN (UGOS Pro) in the RAID calculator and it works out the layout: how much of your drives each RAID level leaves for data. It does not subtract a UGREEN system or file system reserve, because UGREEN has not published one we can cite, and an estimate shown as a vendor figure would be guesswork. The capacity UGOS Pro shows after you create the volume will be somewhat lower than the layout figure.
The calculator also does not know which expansion steps UGOS Pro allows. When you plan adding or replacing drives, it shows the arithmetic and asks you to check that your UGREEN model supports the step.
RAID levels on UGREEN
- RAID 1. A mirror: with two drives, one drive's capacity is usable.
- RAID 5. (n − 1) × the smallest drive. Three drives minimum. Survives one failed drive.
- RAID 6. (n − 2) × the smallest drive. Four drives minimum. Survives two failed drives.
- RAID 10. (n ÷ 2) × the smallest drive, with an even number of drives, four minimum. Survives one failed drive, and up to one per mirror pair.
- RAID 0 / JBOD. No redundancy: one failed drive loses the data on it (RAID 0: all of it).
The formulas assume identical drives and give layout capacity before UGOS Pro's own overhead. With mixed sizes, classic RAID counts every drive at the size of the smallest.
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For hardware, AU pricing and buying guidance: UGREEN NAS Australia guide, UGREEN DXP4800 Pro review and UGREEN DXP2800 review.
Finding the real figure on your NAS
- Create the storage pool and volume in UGOS Pro.
- Compare the capacity UGOS Pro reports with the calculator's layout figure for the same drives and RAID level.
- The difference is UGOS Pro's system and file system overhead on your model and firmware.
RAID keeps a NAS running through a drive failure. It is not a backup: deletion, ransomware, a failed rebuild or a dead NAS can still take everything, so keep a separate copy.
Frequently Asked Questions
Why doesn't the RAID calculator subtract a UGREEN system reserve?
The calculator only subtracts reserves a vendor publishes and we can cite: Synology's per-drive system partitions and file system metadata, QNAP's pool, RAID and ext4 reserves, and the OpenZFS reserve. UGREEN has not published a figure, so the result is the layout capacity and the page says so.