Upload and physical location of the application
The physical location of any load balanced application is an important part of the setup. Generally, deploying the application and its configuration files on shared location introduces a single point of failure and prevents node by node updates, but solves deployment differences and configurations synchronization issues.
Because NLB does not handle file synchronization, you can upload your configuration files on a shared location. To avoid single point of failure, you can use Storage area network (SAN) or Network-attached storage (NAS) or you can store your configurations in the database.
Another possible solution is a hybrid mode, where the application is deployed on each node, while the configurations are shared with offline availability and synchronization. For more information about shared configurations and offline files, see Offline Files for Shared Configuration.
In case more than one user works simultaneously on the same Sitefinity CMS project, see Administration: Configure the project's App_Data folder to be on a shared file location.