I want to use Google Cloud's StackDriver integration for health checks and uptime monitoring. I have a web server running on a google instance, available at foo.mydomain.ai. 

**NB:** Port 80 is open to the world, and the tests I did were done from both other Google instances and my home computer. The webserver is a Jetty (Scalatra) instance running within Tomcat 8.

I've setup the health check as follows: 

[![enter image description here](https://i.stack.imgur.com/LOJK2.png)](https://i.stack.imgur.com/LOJK2.png)
[![enter image description here](https://i.stack.imgur.com/SqYzs.png)](https://i.stack.imgur.com/SqYzs.png)

No matter what I do, I get the error 

```
There was an issue connecting to an endpoint of one or more of your resources. This could be due to temporary network issues or trying to connect with a protocol that is not supported by the resource (e.g. trying to connect to an instance though http that does not have a webserver on it)

```

Fetching the same URL with curl gives the proper response: 

```
habitats@me:~/foobar curl http://foo.mydomain.ai/health/barservice
OK%

```

Fetching using plain GET also works as shown in [![enter image description here](https://i.stack.imgur.com/nqWlS.png)](https://i.stack.imgur.com/nqWlS.png)