When considering how much disk space is required for Encryption Management Server, please note that when backups are running they require a significant percentage of free disk space.
This is because backups include:
Each set of files are compressed separately and then compressed again into a single file.
By default, backup files are stored locally. Clearly, this should be changed so that they are uploaded to a remote server using SCP or FTP. However, even if backups are stored on a remote server, disk space is required to create each backup file before it is transferred to the remote host.
Symantec Encryption Management Server 10.5 and above.
Backup settings can be found in the administration console under System / Backups. Clicking on the Backup Location button allows you to specify whether backups are encrypted to the Organization Key. This is recommended, especially if backups are uploaded to a remote server.
Backup file compression is enabled by default. Disabling compression will result in the fastest backups but if you disable compression you cannot encrypt to the Organization Key.
Encryption Management Server allows you to specify whether you want faster or slower backups using a slider control:
The slider control changes the compression level used during the backup file creation process. The default is for faster backup speeds at the expense of both the size of the completed backup file and the amount of temporary disk space required for the creation of that backup file.
To estimate how much temporary disk space will be needed to create a backup using the default settings, check the size of a recent completed backup from the list under System / Backups and multiply by 3. Therefore if the completed backup file size is 300 MB, assume that 900 MB of temporary space will be needed to create that file.
On its slowest setting, backups will take considerably longer but should result in about a 25% reduction in both final backup size and temporary space requirements.
On its fastest setting, backups will complete perhaps 15% faster than the default settings and the final backup file size can be 20% larger. However, the temporary space required will be far larger. Temporary space requirements can be up to 20 times the size of the completed backup file. This is because compression will only be used at the very end of the backup process. Therefore only use the fastest setting if disk space is not an issue and backups cannot be completed before the start of the next business day.
Please see article 172483 for recommendations on how to reduce the amount of data being backed up.