A robust Blazor app must handle the 'Internet is down' scenario gracefully. This is known as Circuit Management.
By default, Blazor Server shows a gray overlay with 'Attempting to reconnect' text. You can customize this UI to match your brand. More importantly, you can optimize the **Retry Strategy** to be more aggressive or more patient depending on your user's network environment.
If the user loses their connection for more than the DisconnectedCircuitRetentionPeriod, their state is gone. To prevent user frustration, you should persist critical form state to **LocalStorage** frequently. When the user reconnects to a *new* circuit, your app can re-read the state from the browser and restore their progress.
Q: "How many concurrent circuits can one server handle?"
Architect Answer: "On a standard 8GB RAM server, you can typically handle **2,000 to 5,000 concurrent users**. The bottleneck is usually **Memory**, not CPU, because each circuit holds the full state of the user's UI. This is why for public-scale apps, Blazor WASM or a micro-frontend approach is often a better architectural choice."