Private uptime checks with TCP?

[LPrackiNC]

Hi, I've been testing uptime checks on one of my projects and wanted to set up a private uptime check. 

I managed to do it with a TCP probe and it works like a charm. However, the documentation says the following: "Don't select TCP for a private uptime check." Does anybody know why it is discouraged?

I've googled for it, but couldn't find a relevant reason. I'd be grateful to hear from someone more experienced on that topic.

[VishalBulbule · Accepted solution]

@LPrackiNC 

What I understand from my previous experience is TCP health checks only check if the TCP connection can be established between the load balancer and the backend instance. They do not verify that the application on the backend instance is actually functioning correctly.

HTTP and HTTPS health checks not only verify that the TCP connection can be established but also check if the backend instance is responding with a valid HTTP or HTTPS response.

So for accurate health check we should select HTTP/HTTPS.