You can rename a media server pool at any time.
To rename a media server pool
On the central administration server's navigation bar, click Media Servers.
Right-click the media server pool that you want to rename, and then click Rename.
When prompted, enter a new name for the media server pool.
Click OK.
The media server pool is renamed.
More Information
Adding managed media servers to a media server pool in CASO
Creating a media server pool in CASO
Removing a managed media server from a media server pool in CASO