MikroTik failover is the redirection of traffic to the backup line when the main internet line is unavailable. A sound design controls not only the plug-in of the cable, but also the access to specified targets and the behavior of applications when switching lines.
Which fault should the backup line cover?
The modem shutting down, the operator's external access being cut off, and a particular application being inaccessible are not the same malfunction. It must be determined which situation the control will detect. Just being able to reach the nearby gateway does not mean that the target application on the internet is also working.
If two lines depend on the same physical route or the same energy point, they may be affected by a common fault. When evaluating redundancy, don't just compare operator names.
How to monitor line health?
Route priorities and access controls can be used together on the RouterOS. In MikroTik's example, main and backup routes are evaluated over access to remote targets. Target selection and error detection conditions must be adjusted for the real network.
Technical reference: MikroTik — WAN backup and failover.
False switching may occur when the control target itself temporarily becomes unresponsive. How multiple controls will be interpreted and the condition for making the line a main road again must be defined from the beginning.
Are sessions preserved when changing lines?
Existing sessions may need to be re-established on connections whose exit IP address changes. The return of the internet and the uninterrupted continuation of a video meeting, bank session or VPN are not the same criteria of acceptance.
Example scenario: employees can open web pages, but the file application does not work because the branch VPN cannot be established with the address of the backup line. Therefore, create the test list from real business applications.
How to record a failover test?
- Make the main line inaccessible in a controlled manner and monitor the passage.
- Control web, DNS, remote access and critical applications separately.
- Verify the return behavior when the main line returns.
- In case of intermittent fault, examine for continuous line switching.
- Record the test date, targets used, and any open issues.
Your line and application information MikroTik management You can create a transition plan suitable for your institution by evaluating it within the scope of the project.
Related resources
Official sources
Technical documentation and legislation may change; The relevant version and current text should be checked before application.
Frequently Asked Questions
Does the second internet line alone provide redundancy?
No. Route, NAT, DNS and application access must also work over the backup line.
Is failover the same as load balancing?
Failover switches to another path in case of failure; load balancing can use multiple lines for traffic distribution.