HDDs are not required for normal operation, however they expand the functionality by enabling things such as video recording from UniFi Protect, and call recordings and voicemails from UniFi Talk.
We strongly recommend using the UniFi 8TB HDD for UniFi OS Consoles with a 3.5” HDD bay (UDM Pro, UDM SE, UNVR, and UNVR-Pro). These are specialized, industrial-grade drives that can support continuous read and write operations required by a video surveillance system.
Cloud Keys (UCK-G2-PLUS) require a 2.5” HDD for which we strongly recommend continuing to use the drive shipped natively with your equipment. If it will be replaced, the Toshiba 2.5″ 5400RPM 1TB HDD (MQ01ABD100V) appears most stable according to internal testing.
Incorrect drives will result in premature failure which can degrade your entire network’s performance, as well as prevent remote management.
Third-party Drives
If you insist on using a third-party drive, it should meet the following criteria:
- It fits inside the HDD tray
- 3.5” for Dream Machines and Network Video Recorders
- 2.5” for the UCK Gen2 Plus
- It is a surveillance-grade drive designed for continuous load
- These are generally 7200RPM, CMR Drives. SMR drives are not recommended and may lead to performance issues, loss of video footage, or even system crashes.
- It offers at least 1 TB of storage. No maximum HDD capacity has been established.
If you’re using multiple HDDs with your UniFi OS Console, they must all be the same size.
The total usable storage capacity will be affected based on whether either the redundancy level is set to One Disk (RAID1 / RAID5) or Half of Disks (RAID10).
Incompatible HDDs
Some hard drives require an additional 12V external power supply. These hard drives are not supported by the UCK Gen2 Plus or the UNVR.
The following is a list of 3.5” drives that are confirmed to be incompatible with our UniFi OS Consoles:
| Vendor | Series | Model | Capacity | Notes |
| Seagate | SkyHawk | ST10000VX0004 | 10TB | Does not fit the drive tray. |
| Seagate | Ultrathin | ST500LT032 | 500GB | Does not have bottom screws. |
| Western Digital | UltraSlim | WD5000MPCK | 500GB | Does not have bottom screws and connectors do not fit the tray. |
| Any | Any | SMR Drives | Any | Drives fit the tray but cause issues. |
If you have questions about a particular hard drive or need help choosing a hard drive, please reach out to the Ubiquiti Community for insights and recommendations.
Source :
https://help.ui.com/hc/en-us/articles/360037340954-UniFi-HDD-Requirements-and-Compatibility