diff --git a/_data/engine-cli/docker_build.yaml b/_data/engine-cli/docker_build.yaml index 0b248085ea..4006e80197 100644 --- a/_data/engine-cli/docker_build.yaml +++ b/_data/engine-cli/docker_build.yaml @@ -707,7 +707,17 @@ examples: |- more `--add-host` flags. This example adds a static address for a host named `docker`: - $ docker build --add-host=docker:10.180.0.1 . + ```console + $ docker build --add-host docker:10.180.0.1 . + ``` + + If you need your build to connect to services running on the host, you can use + the special `host-gateway` value for `--add-host`. In the following example, + build containers resolve `host.docker.internal` to the host's gateway IP. + + ```console + $ docker build --add-host host.docker.internal:host-gateway . + ``` ### Specifying target build stage (--target) {#target} diff --git a/_data/engine-cli/docker_run.yaml b/_data/engine-cli/docker_run.yaml index a2cdde234d..310c2ac182 100644 --- a/_data/engine-cli/docker_run.yaml +++ b/_data/engine-cli/docker_run.yaml @@ -1703,24 +1703,27 @@ examples: |- round-trip min/avg/max = 92.209/92.495/93.052 ms ``` - Sometimes you need to connect to the Docker host from within your - container. To enable this, pass the Docker host's IP address to - the container using the `--add-host` flag. To find the host's address, - use the `ip addr show` command. + The `--add-host` flag supports a special `host-gateway` value that resolves to + the internal IP address of the host. This is useful when you want containers to + connect to services running on the host machine. - The flags you pass to `ip addr show` depend on whether you are - using IPv4 or IPv6 networking in your containers. Use the following - flags for IPv4 address retrieval for a network device named `eth0`: + It's conventional to use `host.docker.internal` as the hostname referring to + `host-gateway`. Docker Desktop automatically resolves this hostname, see + [Explore networking features](/desktop/networking/#i-want-to-connect-from-a-container-to-a-service-on-the-host). + + The following example creates a simple HTTP server that serves a file from the + host to a container. ```console - $ HOSTIP=`ip -4 addr show scope global dev eth0 | grep inet | awk '{print $2}' | cut -d / -f 1 | sed -n 1p` - $ docker run --add-host=docker:${HOSTIP} --rm -it debian + $ echo "hello from host!" > ./hello + $ python3 -m http.server 8000 + Serving HTTP on 0.0.0.0 port 8000 (http://0.0.0.0:8000/) ... + $ docker run \ + --add-host host.docker.internal:host-gateway \ + curlimages/curl -s host.docker.internal:8000/hello + hello from host! ``` - For IPv6 use the `-6` flag instead of the `-4` flag. For other network - devices, replace `eth0` with the correct device name (for example `docker0` - for the bridge device). - ### Set ulimits in container (--ulimit) {#ulimit} Since setting `ulimit` settings in a container requires extra privileges not diff --git a/config/daemon/prometheus.md b/config/daemon/prometheus.md index c056b63075..91e82d9df2 100644 --- a/config/daemon/prometheus.md +++ b/config/daemon/prometheus.md @@ -57,22 +57,11 @@ Docker now exposes Prometheus-compatible metrics on port 9323. ## Configure and run Prometheus -Prometheus runs as a Docker service on a Docker swarm. +Prometheus runs as a Docker service on a Swarm. -Copy one of the following configuration files and save it to -`/tmp/prometheus.yml` (Linux or Mac) or `C:\tmp\prometheus.yml` (Windows). This -is a stock Prometheus configuration file, except for the addition of the Docker -job definition at the bottom of the file. Docker Desktop for Mac and Docker Desktop for Windows -need a slightly different configuration. - - - -
-
+Copy the following configuration file and save it to a location of your choice, +for example `/tmp/prometheus.yml`. This is a stock Prometheus configuration file, +except for the addition of the Docker job definition at the bottom of the file. ```yml # my global config @@ -101,47 +90,7 @@ scrape_configs: # scheme defaults to 'http'. static_configs: - - targets: ['localhost:9090'] - - - job_name: 'docker' - # metrics_path defaults to '/metrics' - # scheme defaults to 'http'. - - static_configs: - - targets: ['localhost:9323'] -``` - -
-
- -```yml -# my global config -global: - scrape_interval: 15s # Set the scrape interval to every 15 seconds. Default is every 1 minute. - evaluation_interval: 15s # Evaluate rules every 15 seconds. The default is every 1 minute. - # scrape_timeout is set to the global default (10s). - - # Attach these labels to any time series or alerts when communicating with - # external systems (federation, remote storage, Alertmanager). - external_labels: - monitor: 'codelab-monitor' - -# Load rules once and periodically evaluate them according to the global 'evaluation_interval'. -rule_files: - # - "first.rules" - # - "second.rules" - -# A scrape configuration containing exactly one endpoint to scrape: -# Here it's Prometheus itself. -scrape_configs: - # The job name is added as a label `job=` to any timeseries scraped from this config. - - job_name: 'prometheus' - - # metrics_path defaults to '/metrics' - # scheme defaults to 'http'. - - static_configs: - - targets: ['host.docker.internal:9090'] # Only works on Docker Desktop for Mac + - targets: ['host.docker.internal:9090'] - job_name: 'docker' # metrics_path defaults to '/metrics' @@ -151,91 +100,26 @@ scrape_configs: - targets: ['host.docker.internal:9323'] ``` -
-
- -```yml -# my global config -global: - scrape_interval: 15s # Set the scrape interval to every 15 seconds. Default is every 1 minute. - evaluation_interval: 15s # Evaluate rules every 15 seconds. The default is every 1 minute. - # scrape_timeout is set to the global default (10s). - - # Attach these labels to any time series or alerts when communicating with - # external systems (federation, remote storage, Alertmanager). - external_labels: - monitor: 'codelab-monitor' - -# Load rules once and periodically evaluate them according to the global 'evaluation_interval'. -rule_files: - # - "first.rules" - # - "second.rules" - -# A scrape configuration containing exactly one endpoint to scrape: -# Here it's Prometheus itself. -scrape_configs: - # The job name is added as a label `job=` to any timeseries scraped from this config. - - job_name: 'prometheus' - - # metrics_path defaults to '/metrics' - # scheme defaults to 'http'. - - static_configs: - - targets: ['host.docker.internal:9090'] # Only works on Docker Desktop for Windows - - - job_name: 'docker' - # metrics_path defaults to '/metrics' - # scheme defaults to 'http'. - - static_configs: - - targets: ['host.docker.internal:9323'] -``` - -
-
- - Next, start a single-replica Prometheus service using this configuration. - +- If you're using Docker Desktop, run: -
+ ```console + $ docker service create --replicas 1 --name my-prometheus \ + --mount type=bind,source=/tmp/prometheus.yml,destination=/etc/prometheus/prometheus.yml \ + --publish published=9090,target=9090,protocol=tcp \ + prom/prometheus + ``` -
+- If you're using Docker Engine without Docker Desktop, run: -```console -$ docker service create --replicas 1 --name my-prometheus \ - --mount type=bind,source=/tmp/prometheus.yml,destination=/etc/prometheus/prometheus.yml \ - --publish published=9090,target=9090,protocol=tcp \ - prom/prometheus -``` - -
-
- -```console -$ docker service create --replicas 1 --name my-prometheus \ - --mount type=bind,source=/tmp/prometheus.yml,destination=/etc/prometheus/prometheus.yml \ - --publish published=9090,target=9090,protocol=tcp \ - prom/prometheus -``` - -
-
- -```powershell -PS C:\> docker service create --replicas 1 --name my-prometheus - --mount type=bind,source=C:/tmp/prometheus.yml,destination=/etc/prometheus/prometheus.yml - --publish published=9090,target=9090,protocol=tcp - prom/prometheus -``` - -
-
+ ```console + $ docker service create --replicas 1 --name my-prometheus \ + --mount type=bind,source=/tmp/prometheus.yml,destination=/etc/prometheus/prometheus.yml \ + --publish published=9090,target=9090,protocol=tcp \ + --add-host host.docker.internal:host-gateway \ + prom/prometheus + ``` Verify that the Docker target is listed at http://localhost:9090/targets/. diff --git a/desktop/faqs/general.md b/desktop/faqs/general.md index f09dac3b51..631b0ac953 100644 --- a/desktop/faqs/general.md +++ b/desktop/faqs/general.md @@ -96,7 +96,9 @@ For details, see [Docker Engine API](../../engine/api/index.md). ### How do I connect from a container to a service on the host? -Mac, Linux, and Windows have a changing IP address (or none if you have no network access). On both Mac and Windows, we recommend that you connect to the special DNS name `host.docker.internal`, which resolves to the internal IP address used by the host. This is for development purposes and does not work in a production environment outside of Docker Desktop. +The host has a changing IP address, or none if you have no network access. +We recommend that you connect to the special DNS name `host.docker.internal`, +which resolves to the internal IP address used by the host. For more information and examples, see [how to connect from a container to a service on the host](../networking.md#i-want-to-connect-from-a-container-to-a-service-on-the-host). diff --git a/desktop/networking.md b/desktop/networking.md index 9e64700f9a..95841dae5b 100644 --- a/desktop/networking.md +++ b/desktop/networking.md @@ -108,9 +108,9 @@ However if you are a Windows user, it works with Windows containers. ### I want to connect from a container to a service on the host -The host has a changing IP address, or none if you have no network access. We recommend that you connect to the special DNS name -`host.docker.internal` which resolves to the internal IP address used by the -host. This is for development purpose and does not work in a production environment outside of Docker Desktop. +The host has a changing IP address, or none if you have no network access. +We recommend that you connect to the special DNS name `host.docker.internal`, +which resolves to the internal IP address used by the host. You can also reach the gateway using `gateway.docker.internal`.