Many businesses pay for a second internet connection and assume they are protected. Then the main line fails, and everything stops anyway. The second line was there. Nothing was set up to use it.
What real failover needs
- Two different paths. Two services from different providers, ideally entering the building by different routes. Two lines in the same conduit fail together.
- Automatic switching. The firewall has to notice the failure and move traffic without anyone touching it.
- Detection that works. A line can be “up” and still carry no traffic. The equipment should test whether the internet is actually reachable.
- Services that survive the switch. Phones, VPN connections and anything that relies on your public address need to be planned for the backup line too.
What to decide in advance
A backup line is often slower. Decide what must keep working on it: phones, card payments, the order system. Everything else can wait. If your backup is a cellular connection, check the data allowance before you rely on it for a full day.
Test it
Schedule a test outside busy hours. Unplug the main connection and watch. Time how long the switch takes. Make a call, take a payment, connect to the VPN. Then plug it back in and confirm that traffic returns. Repeat the test once or twice a year, and after any change to the network. A failover that has never been tested is a hope.
Related service: Networking & wireless.