Draytek Vigor2136 Series User Manual page 49

By default, the system offers standard health check options such as Google DNS, CloudFlare DNS,
and Quad9 DNS.
Take Google DNS as an example. This profile indicates that primary/secondary IPv4 target
(8.8.8.8/8.8.4.4) is used for checking IPv4 network connection, while primary/secondary IPv6 target
(2001:4860:4860::8888, 2001:4860:4860::8844) is used for checking IPv6 network connection.
Network connection detection is performed per 10 seconds. If one of the IPv4 and IPv6 addresses is
detected connection unsuccessfully, it will be judged as checking network connection failure.
To add/edit a profile, click the +Add/Edit link to get the following page.
Available settings are explained as follows:
Item
Profile Name
Detection Method
Description
Enter a name as the Link Health Check profile.
Select the protocol for ping detection.
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