If Sync prevents HDD from sleeping on your NAS, you should try the following:
On Sync 2.2 and later:
- Go to Preferences > Advanced > power_user.
- Set folder_rescan_interval, config_refresh_interval, config_save_interval to some significant value, for example, 18'000 (1 stands for 1 second so 18'000 = 5 hours).
On Sync versions prior to 2.2:
Set folder_rescan_interval, config_refresh_interval and config_save_interval to some significant value, for example, 18'000 (1 stands for 1 second so 18'000 = 5 hours) by following these steps:
- Open your console (or connect to your box via SSH)
- Shut down Sync. When shutting down, do not use "kill -9" option as it may corrupt your DB file
- Find the settings.dat file. This file resides in Sync Storage folder.
- Download python script, intended to change values in bencoded files (wget http://syncapp.bittorrent.com/support/script/btsync_edit_settings_w4.py)
- Run the script with the above mentioned parameters, for example, "python btsync_edit_settings_w4.py settings.dat set folder_rescan_interval 18000"
- Script won't report anything if operation was successful
- Run Sync again
folder_rescan_interval sets how often Sync rescans folder for files' changes.
config_refresh_interval controls how often Sync checks for the info about available trackers and relay servers
config_save_interval controls how often settings are saved to storage
2) Sync logging may also be a factor preventing your NAS from sleeping. Try disabling logging in Sync Preferences -> Advanced, uncheck logging option.
Note that if some nodes are updating files or requesting some data from your NAS - this is going to awake HDD.