Connect() failed (111: Connection refused) while connecting to upstream

1

Hi,
I am using Kong and spring boot applications in Docker
Spring boot app configuration:

server.servlet.context-path=/userservice
server.port=9090
spring.application.name=userservice

Here is the Dockerfile

FROM openjdk:12
ADD target/userservice.jar userservice.jar
EXPOSE 9090
ENTRYPOINT [“java”,“-jar”,“userservice.jar”]

Docker command to push microservice to docker

docker run -p 9090:9090 userservice

APIs added to kong

curl -i -X POST
–url http://localhost:8001/services/
–data ‘name=userservice’
–data ‘url=http://localhost:9090/userservice’

curl -i -X POST
–url http://localhost:8001/services/userservice/routes
–data ‘hosts=api.com’

curl -i -X GET
–url http://localhost:8000/
–header ‘Host: api.com’

2

And the outcome is

*2019/06/12 13:31:13 [error] 39#0: 184849 connect() failed (111: Connection refused) while connecting to upstream, client: 172.18.0.1, server: kong, request: “GET / HTTP/1.1”, upstream: “http://127.0.0.1:9090/userservice”, host: “api.com”

Any clues?
-Rana

3

Docker should be usually running on host ip and not loopback address (127…0.0.1) so replace “localhost” in your service url in your services config to http://:9090/…

4

Thanks mgkong for the response.
That has to be done at nginx configuration inside the docker. right?
Can you please give more insight?

5

In service definition of your Kong server “userservice”, I see the service URL configured is http://localhost:9090/userservice. In this service URL, try replacing “localhost” with actual IP address of the host where this upstream services (hosted on docker) is running.

6

thanks mgkong. i tried the both public ip and local network ip without any success

7

when i do docker inspect on my spring boot container below o/p observed

“Gateway”: “172.17.0.1”,
“IPAddress”: “172.17.0.2”,
“IPPrefixLen”: 16,
“IPv6Gateway”: “”

i logged in to KONG container and curl the above ip’s, i see one 302 and another one connection refused

/ # curl -i -H “Accept: application/json” -H “Content-Type: application/json” -X GET http://172.18.0.1:9090/userservice

**HTTP/1.1 302 **

Location : http://172.18.0.1:9090/userservice/

Transfer-Encoding : chunked

Date : Sat, 15 Jun 2019 03:14:07 GMT

and when i do the same on 172.18.0.2

/ # curl -i -H “Accept: application/json” -H “Content-Type: application/json” -X GET http://172.18.0.2:9090/userservice

curl: (7) Failed to connect to 172.18.0.2 port 9090: Connection refused

but i can see from my host machine browser

http://localhost:9090/userservice/ is working fine

any thing i miss here

8 
i think the network ip is different in diff networks here


"NetworkSettings": {
            "Bridge": "",
            "SandboxID": "dbadc3aed953f3b08666c4ae43164a5d33740300f2b58a938ae8f60f1c556402",
            "HairpinMode": false,
            "LinkLocalIPv6Address": "",
            "LinkLocalIPv6PrefixLen": 0,
            "Ports": {
                "9090/tcp": [
                    {
                        "HostIp": "0.0.0.0",
                        "HostPort": "9090"
                    }
                ]
            },
            "SandboxKey": "/var/run/docker/netns/dbadc3aed953",
            "SecondaryIPAddresses": null,
            "SecondaryIPv6Addresses": null,
            "EndpointID": "",
            "Gateway": "",
            "GlobalIPv6Address": "",
            "GlobalIPv6PrefixLen": 0,
            "IPAddress": "",
            "IPPrefixLen": 0,
            "IPv6Gateway": "",
            "MacAddress": "",
            "Networks": {
                "kong-net": {
                    "IPAMConfig": null,
                    "Links": null,
                    "Aliases": [
                        "524b0361c5c6"
                    ],
                    "NetworkID": "fad502a41154a6422a3270a859eae6c048316fb959ad54d664ad37b49051fa47",
                    "EndpointID": "6b35cf7d1535db925a720013f0b647695e1cde7c2a257b14a12972107c216858",
                    "Gateway": "172.18.0.1",
                    "IPAddress": "172.18.0.4",
                    "IPPrefixLen": 16,
                    "IPv6Gateway": "",
                    "GlobalIPv6Address": "",
                    "GlobalIPv6PrefixLen": 0,
                    "MacAddress": "02:42:ac:12:00:04",
                    "DriverOpts": null
                }
            }
        }
9

i managed to solve the issue. the change worked here is i removed exposure the Spring boot app to the outside world
Changed
docker run -p 9090:9090 userservice

to

   docker run -d --name userservice \
              --net kong-net \
              userservice
1 Like
10

Thank you! It took me 3 days of searching to find this solution.
I am using docker compose for 2 services + kong gateway. I commented out the ports for the services in the docker compose file and I am no longer getting Connection refused.