What you’re seeing
- The primary ISP goes down and the office loses internet even though the backup line is connected and lit.
- Failover happens, but only after many minutes or not until someone reboots the firewall.
- The main connection is technically up but slow or dropping packets, and the firewall never switches.
- After failover, VPNs, phones or cloud apps still fail while basic browsing works.
- Traffic never returns to the main line once it is restored.
Common causes
Every environment is different, but these are the causes our engineers find most often:
- Failover is triggered only by the physical link going down, so an ISP outage beyond the modem is never detected.
- Health checks are pinging the ISP's own modem or gateway, which keeps responding during an upstream outage.
- The backup interface has no outbound NAT, policy or routing rule, so traffic cannot leave through it.
- Site-to-site VPNs and VoIP trunks are tied to the primary public IP and cannot follow traffic to the backup line.
- The backup service, such as a cellular modem, is suspended, out of data or has an expired plan.
- Load-balancing settings send traffic to both lines in a way that breaks sessions when one fails.
Why it matters
A backup internet line is insurance, and insurance that does not pay out is wasted money. When failover does not work, the business loses internet, phones, cloud apps and card processing during exactly the outage it planned for. Many offices only discover the gap when the main line fails during business hours. Even partial failover can be costly if the phone system or VPN does not move over, because customers still cannot reach you while staff believe the problem is solved.
How AskTechGurus fixes it
Skip the trial and error. A certified engineer works on your actual system, finds the root cause, and fixes it properly.
Tell us what’s happening
Submit a ticket in about two minutes. Paste the error, describe what changed, and pick your tier. No charge to submit.
A certified engineer diagnoses it
A vetted, US-based systems engineer claims your ticket, usually within minutes during business hours, and investigates over a secure remote session you can watch and end at any time.
Fixed and verified with you
The engineer resolves the root cause and confirms with you that it’s working. You don’t just get a workaround, and you get a plain-English summary of what was wrong.
Pay only when it’s resolved
Fixed price from $99, invoiced only after you approve the fix. If it isn’t resolved, you don’t pay.
Frequently asked questions
How do we know failover will work before the next outage?
The only reliable way is a controlled test, such as disconnecting the primary line after hours and watching what keeps working. Many businesses have never run that test.
Will our phones keep working on the backup line?
Only if the phone system and provider are set up to accept traffic from the backup address. Hosted phone systems often need extra configuration to survive a failover.
Can AskTechGurus set up proper failover?
A certified US engineer can review and correct your firewall's failover settings through a remote secure session. Service starts at $99 and you pay only when failover is working.