Hi Site24x7,

Imagine the following situation:

A Web Monitor is configured.
Check Frequency is 1 minute.
Downtime Notification Delay is 2 continuous failures.
Let’s assume our web site gives a 503 HTTP response. Web Monitor checks it for the first time and marks it as DOWN but doesn’t send a notification. In a minute it checks site for the second time and sends a web hook to a third party solution to create an Incident. Then in 5 minutes site gives 200 HTTP response and Web Monitor immediately marks its state as UP and closes the Incident (using web hook). But in 1 minute web site gives 503 HTTP response again. Monitor marks it as DOWN and in 1 minute it opens a new Incident. If we had a delay for UP state we would prevent this "flickering" and wouldn’t close previous Incident and open a new one spamming our third party notification system. Many web servers/reverse proxies/load balancers have such feature enabled.

For example Nginx can use the following configuration:
location / {
    proxy_pass backend;
    health_check interval=10 fails=3 passes=2;
}
The fails parameter requires the server to fail three health checks to be marked as unhealthy (its an analog of Downtime Notification Delay in Site24x7). The passes parameter means the server must pass two consecutive checks to be marked as healthy again (no analog in Site24x7).

AWS ELB (Elastic Load Balancer) also uses 2 parameters - UnhealthyThresholdCount (the number of consecutive failed health checks required before considering a target unhealthy, analog of Downtime Notification Delay) and HealthyThresholdCount (the number of consecutive successful health checks required before considering an unhealthy target healthy, no analog in Site24x7).

Could you please add this feature?

Best regards,
Svyatoslav.