Why You Shouldn’t Use Your NAS Server’s Sync Feature

Many NAS devices are seriously under-powered and the software that ships with it tends to be substandard, at the very least and almost always is not of server-grade quality. What do mean by server-grade? A server-grade software tool uses extensive error control, tracing, and logging, along with countless “sanity checks” behind the scenes to ensure that all processes actually run properly and produce the desired results.

Here is an example related to sync features that aren’t quite server-grade. Some of our customers used to deploy NAS servers with a internet-capable sync feature before switching to BackupChain. The problem was that they didn’t know that was an issue with their synchronization. What was the problem? The problem was that the sync wasn’t always running properly, or not at all. It would skip files, stop in the middle and leave out folder structures. To make things worse, there was no log or notification mechanism. The developers of that NAS apparently wrote the software as if digital systems never ever fail, as if connection links never break, the file system never corrupts, and hard disk sectors never go bad. One day when their main NAS broke they discovered the hard way that their backup NAS was not up-to-date for a very long time. Unfortunately no one noticed but also technically there wasn’t a way to find out that it was, other than by comparing folder contents manually on each NAS, which is obviously not a workable solution.

When you are dealing with important information, it makes sense to rely on time-tested, server-grade software solutions that actually work reliably under all reasonably to be expected circumstances. You will want your tools to provide a log and various notification features, so that the IT administrators will be alerted in the case of malfunction. In addition, when you back up a server on Windows, our backup solution uses a mechanism that provides a consistent view of the entire storage at a specific point in time. Many NAS devices do not offer such a feature, but it’s a critical mechanism, especially for large file servers. Imagine a folder structure with millions of files and folders. The NAS sync process might take hours to process it. In the meantime, users may change, delete, rename, and add files as they wish. The result is that the backed up content doesn’t match any particular point in time of the original, i.e. compared to the source. The folder structure on the backup NAS ends up being inconsistent. A consistent backup is a “freeze” of the folder structure, so that no matter what users change while the backup is running, and no matter how long the backup takes, the backup is guaranteed to be consistent and it reflects the complete content on the original server at a very specific point in time. Even if NAS sync features were reliable, without the consistency feature the NAS sync features are worthless for critical business data and therefore not recommended.