Cannot access host machine from docker container - docker

Question

Using docker version 18.09.2. Using docker on windows 10.
Setting up a prometheus and grafana stack to monitor metrics on a service running on my localhost. Here's my docker compose file.
version: '3.4'
networks:
monitor-net:
driver: bridge
dockernet:
external: true
volumes:
prometheus_data: {}
grafana_data: {}
services:
prometheus:
image: prom/prometheus:v2.7.1
container_name: prometheus
volumes:
- ./prometheus/:/etc/prometheus/
- prometheus_data:/prometheus
command:
- '--config.file=/etc/prometheus/prometheus.yml'
- '--storage.tsdb.path=/prometheus'
- '--web.console.libraries=/etc/prometheus/console_libraries'
- '--web.console.templates=/etc/prometheus/consoles'
- '--storage.tsdb.retention.time=200h'
- '--web.enable-lifecycle'
restart: unless-stopped
expose:
- 9090
networks:
- monitor-net
- dockernet
extra_hosts:
- "localhost1:10.0.75.1"
labels:
org.label-schema.group: "monitoring"
grafana:
image: grafana/grafana:5.4.3
container_name: grafana
volumes:
- grafana_data:/var/lib/grafana
- ./grafana/datasources:/etc/grafana/datasources
- ./grafana/dashboards:/etc/grafana/dashboards
- ./grafana/setup.sh:/setup.sh
entrypoint: /setup.sh
environment:
- GF_SECURITY_ADMIN_USER=${ADMIN_USER:-admin}
- GF_SECURITY_ADMIN_PASSWORD=${ADMIN_PASSWORD:-admin}
- GF_USERS_ALLOW_SIGN_UP=false
restart: unless-stopped
expose:
- 3000
networks:
- monitor-net
- dockernet
labels:
org.label-schema.group: "monitoring"
caddy:
image: stefanprodan/caddy
container_name: caddy
ports:
- "3000:3000"
- "9090:9090"
- "9093:9093"
- "9091:9091"
volumes:
- ./caddy/:/etc/caddy/
environment:
- ADMIN_USER=${ADMIN_USER:-admin}
- ADMIN_PASSWORD=${ADMIN_PASSWORD:-admin}
restart: unless-stopped
networks:
- monitor-net
- dockernet
labels:
org.label-schema.group: "monitoring"
Here is my prometheus.yml file.
global:
scrape_interval: 15s
evaluation_interval: 15s
# Attach these labels to any time series or alerts when communicating with
# external systems (federation, remote storage, Alertmanager).
external_labels:
monitor: 'docker-host-alpha'
# Load and evaluate rules in this file every 'evaluation_interval' seconds.
rule_files:
- "alert.rules"
# A scrape configuration containing exactly one endpoint to scrape.
scrape_configs:
- job_name: 'prometheus'
scrape_interval: 10s
static_configs:
- targets: ['localhost:9090']
- job_name: 'myapp'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['docker.for.win.localhost:32771']
- job_name: 'myapp1'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['docker.for.win.host.internal:51626']
- job_name: 'myapp2'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['docker.for.win.host.internal.localhost:51626']
- job_name: 'myapp3'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['docker.for.win.host.localhost:51626']
- job_name: 'myapp4'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['docker.for.win.localhost:51626']
- job_name: 'myapp5'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['host.docker.internal:51626']
- job_name: 'myapp6'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['host.docker.internal.localhost:51626']
- job_name: 'myapp7'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['docker.for.win.localhost:51626']
- job_name: 'myapp8'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['127.0.0.1:51626']
- job_name: 'myapp9'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['localhost:51626']
- job_name: 'myapp10'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['10.0.75.1:51626']
- job_name: 'myapp12'
scrape_interval: 10s
metrics_path: /metrics
static_configs:
- targets: ['localhost1:51626']
From what I understand host.docker.internal should reference my host IP and give me access to my local app but it didn't. So then I looked up my docker NAT IP address with ipconfig (the 10.0.75.1 address) and that didn't work either.
Then I tried the network binding of localhost1 to 10.0.75.1. I tried setting up a bridge network called dockernet and connect that way and it didn't work. When I launch my app in a docker container I can get to it through "docker.for.win.localhost:32771" but this container can't access my remote database so that's why I need it to run local.
Prometheus gives the following responses for some of the respective addresses:
Endpoint: Error
http://docker.for.win.localhost:32771/metrics: UP
http://host.docker.internal:51626/metrics: server returned HTTP status 400 Bad Request
http://docker.for.win.localhost:51626/metrics: server returned HTTP status 400 Bad Request
http://host.docker.internal.localhost:51626/metrics: Get http://host.docker.internal.localhost:51626/metrics: dial tcp: lookup host.docker.internal.localhost on 127.0.0.11:53: no such host
http://docker.for.win.host.internal.localhost:51626/metrics: Get http://docker.for.win.host.internal.localhost:51626/metrics: dial tcp: lookup docker.for.win.host.internal.localhost on 127.0.0.11:53: no such host
I've tried everything and am out of ideas. Can anyone shed some light?

Answer 1

I have the similar problem. I locally run my own application on IIS Express on port 52562, and prometheus inside container show that http://docker.for.win.localhost:52562/metrics return 400 BAD Request.
Problem was that IIS Express listen only for localhost, so I edit bindings in my applicationhost.config from
<binding protocol="http" bindingInformation="*:52562:localhost" />
to
<binding protocol="http" bindingInformation="*:52562:" />
and restart IIS Express.
This fixed the problem.

Answer 2

for my works this
version: "3"
networks:
sandbox:
driver: bridge
services:
prometheus:
restart: always
image: prom/prometheus:v2.3.2
volumes: ["./prometheus/prometheus.yml:/etc/prometheus/prometheus.yml"]
ports: ["9090:9090"]
extra_hosts: ["host.docker.internal:172.17.0.1"] # from Gateway bridge and added /etc/hosts
networks: ["sandbox"]
grafana:
....

Answer 3

You might also check if your windows 10 firewall is blocking the connection.
To disable the firewall completely:
netsh advfirewall set allprofiles state off
To allow a connection on a specific port:
New-NetFirewallRule -Protocol TCP -LocalPort 44369 -Direction Inbound -Action Allow -DisplayName "Allow network TCP on port 44369"