When the agents in your Datto appliance are giving the error “Backup skipped due to not enough free space” it means that your device has reached its full physical capacity and because of this no more backups can be run.

To confirm the status of the used storage, over the Datto portal’s homepage, review the Local Storage Usage section. From there, you’ll see what’s the Local Free space available and how much space each server is using individually. If you sum the usage from all the servers you’ll get the total physical space that was available for your appliance by contract.


Once you’re appliance is full, there are three options that could be considered:


  • Review the local retention for the agents to see if it can be reduced to store backups for less time so this can clear some space.


The first option is to check if the space can be cleared by adjusting the retention time for the backups stored on the appliance. Normally, the best solution is to keep the minimum possible, which is a 1 week retention and this should be enough since the Datto appliance is expected to have the most recent data available for disaster scenarios. Review this option using the instructions below and adjust it as necessary.

  1. Over the Datto web portal, click on the Protect tab.
  2. Select one of the agents on the list and click on Configure Agent Settings.
  3. Scroll to Local Backup and Retention.
  4. On the Set Retention for Local Backups option, modify Keep local backups on my device for 1 week.
  5. Hit on Apply To All to confirm.


  • Delete some of the least important servers so the backups could keep running for the most important ones.


Because of the Datto appliance space limitation you would have to evaluate which servers would be your priority to have backed up in case of a disaster scenario and you would have to choose which ones can be removed to clear space.

In case there are retired servers still being stored on the Datto appliance these would be the first ones that should be deleted, considering that your priority should always be to keep your online servers up to date and the retired machines should not be kept on the local appliance for long term.

To remove the servers that are not needed, follow these instructions:

    1. Over the Datto web portal, click on the Protect tab.
    2. Scroll down the page and find the server in question.
    3. On the left side, choose the option Remove Agent.
    4. Confirm the data deletion as requested.


  • Consider an upgrade for your Datto appliance to a bigger capacity.


If after reviewing the Local Retention it is already set to 1 week and if there are no servers that can be deleted to clear space, the only option to consider then is to upgrade your Datto appliance to have a bigger capacity that could be enough to store the amount of servers that you need to keep.

Please contact Hexistor support to provide you a quotation to upgrade to a new Datto device.