A simple curl command to check, whether your HTTP service works as you want would be
curl -vk https://<IP of your server>[:<Port of your Service>]<URI of your Service>
A full example could be
curl -vk https://192.168.10.15/path/to/my/app
This would result in an HTTP request
GET /path/to/my/app HTTP/1.1 Host: 192.168.10.15 Connection: keep-alive ...
If your server uses name-based Virtual Hosts, you have to adjust the Host-header field, to get the correct response:
curl -vk https//192.168.10.15/path/to/my/app -H "Host: myapp.example.com"
You can set more custom headers with `-H`, if necessary.
curl can only be used within the advanced shell (=Bash). A good practice to check for the health status of your app depends on you. A simple HTTP monitor, which checks the response code of your app is better than a simple tcp check, i.e.
HTTP/1.(0|1) (200|404|403)
would check for a HTTP/1.0 or HTTP/1.1 response, accepting response codes 200, 404 and 403 - for whatever reason this may make sense...
A better approach is a built-in health check in your applications, where the application owner has created an health endpoint, which is callable via HTTP, i.e.
curl -vk https//192.168.10.15/status/health
returns
HTTP/1.1 200 OK ... Content-Type: application/json {"status": "ok"}
These are just some ideas, based on you questions. From my experience such advanced monitors are rare. In the cases I know of, they are mostly simple monitors that only check for response status code 200.
Nimbostratus
