You can manually start a filesystem clean from the CLI:

1. Log into the CLI using SSH (or via serial) using an account with admin privileges.
2. To check how much space you will gain by running the clean, type:

   filesys show space

   The column Cleanable GiB will show the amount of storage that will be cleaned.
3. Start the filesystem clean by typing:

   filesys clean start

4. To monitor the process, type:

   filesys clean watch

   The monitor will run continuously in the CLI. Use Control + C to return to the prompt.

DellEMC offers a free-to-try virtual appliance of DataDomain, allowing you to do a Try & Buy. You can download the appliance here:

https://www.emc.com/products-solutions/trial-software-download/data-domain-virtual-edition.htm

When attempting to log onto a Data Domain's management webpage, sometimes you may run into the issue where you are not able to log on, and the following error appears, even though you have not upgraded the firmware or there's nothing wrong with installed SSL certificates.

Service Not Available
The GUI Service is temporarily unavailable. Please refresh your browser. If the problem persists, please contact DataDomain support for assistance.

While the webpage does not work, it is still possible to log on using CLI (through SSH).

If you have not upgraded DDOS, try restarting the web services by logging on through CLI and running the following commands in sequence:

adminaccess disable httpadm  ...