When the Differing Master Copy rule is selected for a synchronization, SureSync will copy the file from the source path over the destination files if the modified date and time stamp on the source file is different from the destination in any way. This means if the time stamp is older or newer than the destination time stamp. The only time it won't copy is when the files have the same date stamp. A Differing Master Copy rule does not delete files from the destination path.

With a Differing Master Copy rule, if a user makes a chance to a file which exists on the source, the source file will be synchronized over the destination file when the synchronization job is run. However, a user could add files and folders to a destination directory which do not exist on the source and those files would be left alone.

Please note:

 

• Any changes made only to a file on a destination path will be overwritten the next time the files are synchronized with the copy from the source, so if there is a permanent change you want to make it must be made to the source file. There will be no warning.
• This method does not delete files. If you delete the source file manually, the destination file will be left "as is" at the next synchronization (it will not be deleted or replaced). If you delete a destination file manually, the next time the files are synchronized a new copy from the source will be synchronized to the destination. If you want the ability to propagate deletes in a one-way rule, you must choose the mirror rule.

Possible Scenarios

This synchronization method could be used when you want to have files distributed to several machines and you always need the information to match that of the Master version of the file. For example, you want all your sales representatives to have a copy of your inventory database, and to keep it updated you copy a version over to all their machines every night. If one of those people opens their copy of the database to look up an item it will change the modification date, possibly making it more recent then the last change to the Master, but you don't want that to prevent them from getting an up-to-date copy during the next synchronization. With the Differing Master Copy method, SureSync will copy over the file as long as the date stamps are different (not just when the Master is newer) so every night your staff gets the definitive version of the inventory no matter when they last opened their copy.

File Distribution

The Differing Master Copy rule can be used for file distribution scenarios where you want to ensure that any files existing in the folder structure that aren't present on the source remain on the destinations. In situations where you want files on the destinations to be deleted that aren't on the source, use a Mirror instead.

Disaster Recovery and Backup

SureSync is commonly used for disaster recovery and backup purposes. You can run a Schedule or a Real-Time Monitor with a Differing Master Copy rule and protect file changes which occur between tape backups or drive images. The Differing Master Copy rule is ideal for this purpose because the destination files are not deleted if the source file is deleted. For example, if a user accidentally deletes a file from the source, you can still get the file back from the destination when using this rule type.

Summary Chart

The summary chart will give you a breakdown of how the Differing Master Copy rule functions when different events occur.