# Local and remote vaults

If you want to use your notes on different devices, one of the options you have is to Sync your notes across devices. Obsidian offers one such service, Obsidian Sync, that works differently than other syncing services, like iCloud and OneDrive.

Here are some key terms:

• A vault is a folder on your file system which contains notes and an .obsidian folder with Obsidian-specific configuration.
• A local vault is the copy of your vault that exists on each of your devices. When using sync services, you connect these local vaults to enable synchronization.
• A remote vault is centralized storage that local vaults connect to directly through Obsidian Sync.

There are two common approaches to syncing:

• File based sync services: Local vaults must be in monitored folders, sync happens through the file system
• Remote vaults: Centralized storage that local vaults connect to directly through Obsidian

Services like Dropbox, Google Drive, iCloud, and OneDrive are folder-based. These services monitor specific folders and automatically sync any files placed within them. Files must be in the designated cloud-service folders to sync. With file-based sync services, your local vault acts as just another folder being monitored. There is no dedicated remote vault - instead, the cloud storage serves as a passthrough, copying files between local vaults on different devices.

The diagram below shows a simplified version of how these services work:

graph TD
    A[Your active device - file change]
    B[Sync client detects change]
    C[Upload to cloud storage]
    D[Cloud storage]
    E[Other devices check for updates]
    F[Download Changes]
    G[Other device updated]
    
    A --> B
    B --> C
    C --> D
    D --> E
    E --> F
    F --> G
    style A fill:#c6dbef
    style B fill:#dadaeb
    style C fill:#c7e9c0
    style D fill:#fdd49e
    style E fill:#fdcc8a
    style F fill:#fee8c8
    style G fill:#a1dab4

If the cloud service has background syncing, then some of these processes may be happening even when you are not actively using the applications to view the files. These services monitor specific folders and automatically sync any files placed within them. Files must be in the designated cloud-service folders to sync.

Obsidian Sync allows you to create a remote vault that serves as centralized storage through its Obsidian Sync service. This allows you to choose almost any folder on any of your devices to store your files - whether on an external hard drive, in C:\, or in App storage on Android.

However, we do have a list of recommended locations for your local vault if you also use File based sync services on the same device - mainly, anywhere that is not in a third-party syncing service.

The diagram below shows a simplified version of how Obsidian Sync works:

graph TD
   D[Local Vault A]
   L[Local Vault B]
   S[Remote Vault]
   P[Local Vault C]
   T[Local Vault D]
   
   D -->|Upload| S
   S -->|Download| D
   L -->|Upload| S
   S -->|Download| L
   P -->|Upload| S
   S -->|Download| P
   T -->|Upload| S
   S -->|Download| T
   
   style D fill:#c6dbef
   style L fill:#dadaeb
   style S fill:#c7e9c0
   style P fill:#fdd49e
   style T fill:#fdcc8a

The strength of this system becomes more apparent with more device types. File based sync services can be implemented inconsistently across operating systems, and mobile devices have their own rules with how applications can be sandboxed and power throttled, which makes it much harder for traditional file-based services to work seamlessly.

With Obsidian Sync, the service handles synchronization directly through the application, providing consistent behavior regardless of device type or operating system limitations, while prioritizing keeping a local copy of your data as a soft backup.

When you make changes to files in your local vault, Obsidian Sync detects these changes and uploads them to the remote vault. Other devices connected to the same remote vault will then download these changes and apply them to their local vaults. Obsidian Sync tracks changes at the file level and only transfers the files that have been modified, rather than syncing entire folders. This reduces bandwidth usage and sync time.

When conflicts occur or when you need to control which files sync, Obsidian Sync provides specific mechanisms to handle these situations:

Conflict resolution

Sync settings and selective syncing > Selective syncing#Exclude a folder from syncing

Changes made while offline are queued and sync automatically when your device reconnects to the internet and Obsidian is open. Your local vault remains fully functional during offline periods.

• Set up Obsidian Sync to get started with remote vaults.
• Switch to Obsidian Sync if you're currently using file-based sync and want to use Obsidian Sync.
• Explore other sync options if you're still deciding.