Do Not Exclude *.tmp Plus Subdirectories (A043)

It is a good idea to exclude temporary files from LiveVault Online Backup Service backup, as they generate unnecessarily high data change rates and excessive use of network bandwidth. LiveVault Online Backup Service automatically excludes temporary files from root directories, temporary folders, and temporary Internet files for your Agent computers.

However, do not create the following backup exclusion rule for your Agents:

Exclude <vol>:\*.tmp (plus subdirectories)

For example:

Exclude C:\*.tmp (plus subdirectories)
Exclude D:\*.tmp (plus subdirectories)

The effect of the above rules, particularly the "plus subdirectories" is not what you may intend.

Certain applications (such as Microsoft PowerPoint and Word) use temporary files for editing, with the temporary file usually stored in the same subdirectory as the original file. Because of the process the applications use for the editing cycle (for example, rename *.ppt to *.tmp, edits, rename *.tmp to *.ppt), excluding the temporary files from the subdirectories where the editing is taking place can cause LiveVault Online Backup Service to transmit full files whenever those files are edited, instead of just the changes.

Normally (i.e., without the exclusion) LiveVault Online Backup Service sees the application rename the original file to a temporary file (so all information about the original file is transferred to the new temporary file). It then captures the edits to the temporary file. When the application subsequently renames the temporary file back to the original file, LiveVault Online Backup Service handles the rename again. LiveVault Online Backup Service retains knowledge of the file throughout the cycle, and so only transmits the changes.

However, with this exclusion, LiveVault Online Backup Service sees the application rename the original file to a temporary file. But because temporary files are excluded from backup, LiveVault Online Backup Service does not track the file or the changes to it. When the application renames the temporary file back to the original file, LiveVault Online Backup Service transmits the full file again including content, attributes and security (this is called a "rename into policy").