Why does my TNAS device not go into hibernation?

If your hard drives remain idle for a preset length of time, they will go into hibernation. However, some conditions (including volume status, services, and applications) will stop your TNAS device from entering hibernation mode or waking up hard drives from hibernation from time to time. For a newly installed TOS, it will take about 24 to 48 hours for the Btrfs file system to complete the logging and balance operations in its background, while for the EXT 4 file system, it will take about 12 to 24 hours to complete, during which time the hard drives cannot hibernate. The actual time required depends on the hard disk capacity. If you have copied a large number of files to TNAS, it will take longer to log and balance. To learn more about logging and balance, please visit the website https://wiki.archlinux.org/index.php/Btrfs During hibernation of the hard drive, the hard drive indicator will be always on; To confirm whether the hard disk is in hibernation mode, please touch the main body of the device with your hand. If you don't feel any vibration, the hard drive may already be in hibernation.

The reasons for stopping the hard disk from hibernation include:

Volume status stops the hard drive from hibernation ；

The volume is in a degraded or crashed state, and the volume has not been created;

The following services stop the hard drive from going into hibernation:

DDNS (Dynamic Domain Name Service);

LDAP: When your TNAS acts as an LDAP client;

File service: After enabling SMB/AFP/NFS, any SMB/CIFS broadcast packet may prevent the system from entering the hibernation mode, including Windows Explorer running on the same network;

NTP: When using NTP service to synchronize with other network equipment;

Thumbnail and index: When generating thumbnails or re-indexing multimedia files after upgrading;

Windows Media Player: When enabling the network sharing service of Windows Media Player in LAN;

IPv6: After enabling IPv6, your TNAS may wake up from hibernation;

VPN client is enabled;

If many concurrent processes require memory swapping (with the available RAM capacity exceeding the memory capacity, and the hard disk temporarily used for reading/writing cached data), TNAS cannot go to hibernation;

Applications; Cloud synchronization; DNS server; Downloaded applications: Transmission, qBittorrent, and Aria 2; Docker; Mail server; Media server/DLNA media server; Plex media server; Emby media server; Proxy server; VirtualBox; VPN server; WebDAV server; USB Copy device: When connecting any USB device to TNAS.

If you do not want to disable the above-mentioned applications or services but still want to save power, you can set a scheduled power on/off.