Synology NAS drives are popular, and they're great for storing files on your home network, streaming media or backing up your computer. Left unchecked, however, those backups can fill up your available storage in a hurry.
To prevent your backup program from taking up more space than necessary on your Synology NAS drive, set a quota for the Synology account you use to connect to it (in this example, we'll use Time Machine on a Mac). Instead of using your own Synology admin account, create an account just for Time Machine. Then, give it a quota:
- Log in to your Synology NAS drive, then go to Control Panel > User > Create.
- Choose a name and password for the new Time Machine user account.
- Make sure the account is part of the regular users group, not the admin group.
- Give read/write access to the folder you plan to use for Time Machine backups.
- Tick the box to enable a quota for the user, then choose the quota. Two times the total amount of storage on your computer should be sufficient.
- Finish the User Creation Wizard and apply the settings to the new user.
After you finish setting the quota, go to Time Machine (or your backup program of choice) and connect to the Synology shared folder using the user account you just created. Backups will now be restricted to the space you set aside for it, so you don't run out of space for all your other goodies.
How to back up data from Mac to Synology NAS with Time Machine [Synology Support]