Kill switch: block traffic if the tunnel drops
If the tunnel drops, a kill switch blocks traffic instead of letting it leave on the open network. ForestVPN has one in every app, enforced by the operating system, and none of them is absolute.
How it works
- 01
iPhone, iPad, Mac and Apple TV
With the kill switch on, ForestVPN asks the system to send all traffic through the tunnel, and reconnects on every network.
- 02
Android
Android blocks all traffic the instant the VPN connection drops, enforced by the system while ForestVPN is running. Android's own Always-on VPN with Block connections without VPN covers the gaps when the app is stopped.
- 03
Windows and Linux
Local firewall rules, the Windows Filtering Platform on Windows and nftables on Linux, keep anything from leaving while the tunnel is not up. On Linux they stay in place after a restart until you turn the setting off.
What you get
- Traffic stops instead of leaving unprotected when the tunnel drops.
- A setting you choose on each device, with the trade-off explained.
Limits and honest caveats
- No kill switch is absolute. A rule that fails to apply, or an update or another program that removes it, can leave the block missing.
- On iPhone, iPad, Mac and Apple TV the system decides what an app can capture, so a few system services can still go around the tunnel.
- While it blocks, nothing has internet. If you are stuck with no network, reconnect or turn the kill switch off in settings.
Where it exists
- iPhone
- iPad
- Mac
- Apple TV
- Android
- Android TV
- Windows
- Linux
Plans
Free and Premium both have it.
Questions
- Does it protect me if the app crashes?
- On Android, turn on Always-on VPN with Block connections without VPN in Android's settings, and the system blocks traffic even if ForestVPN is killed. On Linux the rules stay in place after a restart until you turn the setting off.
- Why is my internet gone?
- If the tunnel is down and the kill switch is on, traffic is blocked on purpose. Reconnect, or turn the kill switch off in settings.
- Can a kill switch be absolute?
- No, and we do not claim it. The limits above are the ones we know about.