When backing up your Mac to your NAS using Time Machine, we suggest setting a quota to prevent the backup data from taking up too much space on your volume. You can do this via one or both of the methods provided in this article.

Method 1: Assign a user quota

1. Do one of the following according to your DSM version:
   • DSM 7.x: Go to Control Panel > User & Group > User and click Create.
   • DSM 6.x: Go to Control Panel > User and click Create.
2. Enter a username and password. Continue through the wizard.
3. On the Assign shared folders permissions page, assign Read/Write permissions for your Time Machine folder.¹
   
4. On the Assign user quota page, enter a value for the Time Machine folder in the User Quota field and select a unit from the drop-down menu. Click Next.^{2 3}
   
5. On the Assign application permissions page, tick the Allow checkbox for AFP or SMB, depending on which file service you use. Then, click Next.
   DSM 6.x users can skip this step.
   
6. Continue through the next prompts to complete the process.

Method 2: Assign a shared folder quota

1. Go to Control Panel > Shared Folder and select your Time Machine folder.^{1 4}
2. Click Edit and go to the Advanced tab.
3. Tick Enable shared folder quota. Enter a value and select a unit from the drop-down menu.³
   
4. Click Save.