WAN Failover

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WAN Failover

About WAN Failover

WAN Failover works in conjunction with multiple ISPs to assure that you maintain Internet connectivity if a loss of connectivity occurs on one of your WAN connections. If one of your ISP links goes down, Untangle will automatically route all traffic over the other WAN(s) until service is restored. Please note that WAN Failover is not supported if an Untangle WAN interface is set to PPPoE.

You may also consider using WAN Balancer in your network as well - it allows you to maintain an automatic distribution of traffic over multiple WAN links rather than just failing over if one goes down.

Settings

This section reviews the different settings and configuration options available for WAN Failover.

Status

The status tab presents an overview of the WANs and the current test results.

Interface ID: The number of the interface.
Interface Name: The name of the interface in Untangle's GUI.
System Name: The name of the interface as seen by Untangle's OS.
Online Status: True or False whether the WAN is online.
Current Tests Count: The total number of the tests ran on that interface.
Tests Passed: The total number of the tests ran on that interface that passed.
Tests Failed: The total number of the tests ran on that interface that failed.

Tests

WAN Failover must have tests set up for every WAN interface; these tests are set up on the Tests tab. Just click Add, select your interface and test type, then run the test - if it passes, go ahead and save it. Once you have tests set up for each WAN, you're done! The options are as follows:

Interface: The interface you want to set up a test for.
Description: A description for this test.
Testing Interval: Determines how often (in seconds) your specified test will be executed.
Timeout: The maximum amount of time that may pass without receiving a response to your test. This value should be less than the Testing Interval. You should make sure that you allow for enough time to pass if you have a poor connection to the internet, or a connection that often has long latency (delays) associated with it.
Failure Threshold: How many failures are acceptable during the testing period.
Test Type: is the specific method you will use to determine whether failover will be initiated. Test Types are explained below.

Event Log

Use the following terms and definitions to understand the Event Logs:

Test Event Log


Name	Description
Timestamp	The time the event took place.
Interface	The interface involved in this action.
Success	True or false.
Test Description	The type of test used.

Outage Event Log


Name	Description
Start Time	The start time of this event.
End Time	The end time of this event.
WAN	The interface involved in this action.

WAN Failover FAQs

I installed and configured WAN Failover, but nothing is happening. What should I do?

Make sure each ISP's interface has is WAN Interface? checked at Config > Networking > Interfaces and has all of the required information properly entered. You'll also need to verify WAN Failover has tests set up for each WAN connection. If you're only using WAN Failover, you'll need to disconnect your primary WAN to get traffic to flow over the secondary. If you're only using WAN Balancer, make sure your weights are set properly.

Does WAN Failover support PPPoE?

No, PPPoE is not supported in a failover environment.

What tests should I use for Failover?

This is really up to you. Untangle provides four test methods - in each case, Untangle sends out data packets and decides if the WAN is up or down depending on your specified Testing, Timeout and Failure Threshold intervals:

Ping Test: Untangle will ping the specified IP address.
ARP Test: Untangle will ARP for its gateway.
DNS Test: Untangle will make a request to the upstream DNS server.
HTTP Test: Untangle will make a connection to the specified domain name.

Is a ping test better than the HTTP test?

Yes and no - ping tests are simpler and more straight forward than the HTTP test, but many network operators block ping requests because they can be used for Denial of Service attacks. In both cases, you should select IP addresses that are external to your network but relatively close to you. As the number of network hops increases, the chances of encountering a bad or slow link increases. When that happens, Untangle may interpret it as a network problem and report one of your WAN connections as failing.

I only have one internet connection. Why would I want WAN Failover?

With a single WAN connection, its obvious that you have no alternative if your internet connection fails. You can still monitor the uptime of your ISP with WAN Failover by defining a rule that will log service interruptions. If downtime is hurting you financially, WAN Failover can help you document it rather inexpensively.

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