The Sync driver is responsible for quiescing the drive before a snapshot occurs (which happens before the backup).
If your server does not run a database (SQL, Exchange, Oracle, AD), you can implement the LGTO SYNC driver in VMware tools to quiesce the file system. This means your snapshot will contain as much as it can, and no half-open file writes.
Caution: If your server does run a database, do not use the LGTO SYNC driver unless you plan on stopping the database services using the pre-freeze script and starting them again using post-thaw script. If you do not, database services may fail during the
LGTO SYNC freeze operation.
LGTO 同步错误会中断 VMware ESX 3.x/4.x 和 VMware ESXi 4.x 中的远程虚拟机连接