Cron is used to schedule actions. It can be used to automate a number of processes; here I will illustrate how to use it to pause and restart torrents at specific times (downloading 11pm - 5pm only).
Go to: System -> Advanced
Select the Cron tab to the right.
Click on the + symbol at the bottom right of the table.
In Command: substitute your Transmission password set in Services -> BitTorrent in place of password in the commands below.
To start all torrents at 11pm:
/usr/local/bin/transmission-remote -t all -s --auth admin:password
Or, to add download and upload limits in kB/s, just substitute numbers after -d and -u respectively:
/usr/local/bin/transmission-remote -t all -d 20 -u 20 -s --auth admin:password
Description: Start Torrents 11pm
The timing is very customisable: In order to run the command to restart all Transmission torrents at 11pm, select:
Minutes: 0 (Selected) Hours: 23 (Selected) Days: All Months: All Week days: All
This is illustrated below:
Then click Run now and Save to ensure the process works.
To pause all torrents at 5pm, repeat the process (i.e. add another almost identical cron command in the same way):
/usr/local/bin/transmission-remote -t all -S --auth admin:password
And select 5pm (i.e. Minutes 0, Hours 17, All Days, months and Weekdays)
Remember, these cron scheduled tasks can be over-ridden by manually adding, pausing and restarting torrents from the Transmission WebGUI.
For finer control over scheduling with cron, see the reference below.
Ref: FreeNAS forum