dockprom
========

A monitoring solution for Docker hosts and containers with [Prometheus](https://prometheus.io/), [Grafana](http://grafana.org/), [cAdvisor](https://github.com/google/cadvisor),
[NodeExporter](https://github.com/prometheus/node_exporter) and alerting with [AlertManager](https://github.com/prometheus/alertmanager).

***If you're looking for the Docker Swarm version please go to [stefanprodan/swarmprom](https://github.com/stefanprodan/swarmprom)***

## Install

Clone this repository on your Docker host, cd into dockprom directory and run compose up:

```bash
git clone https://github.com/stefanprodan/dockprom
cd dockprom

ADMIN_USER=admin ADMIN_PASSWORD=admin docker-compose up -d
```

Prerequisites:

* Docker Engine >= 1.13
* Docker Compose >= 1.11

Containers:

* Prometheus (metrics database) `http://<host-ip>:9090`
* Prometheus-Pushgateway (push acceptor for ephemeral and batch jobs) `http://<host-ip>:9091`
* AlertManager (alerts management) `http://<host-ip>:9093`
* Grafana (visualize metrics) `http://<host-ip>:3000`
* NodeExporter (host metrics collector)
* cAdvisor (containers metrics collector)
* Caddy (reverse proxy and basic auth provider for prometheus and alertmanager)

## Setup Grafana

Navigate to `http://<host-ip>:3000` and login with user ***admin*** password ***admin***. You can change the credentials in the compose file or by supplying the `ADMIN_USER` and `ADMIN_PASSWORD` environment variables on compose up. The config file can be added directly in grafana part like this
```
grafana:
  image: grafana/grafana:7.2.0
  env_file:
    - config

```
and the config file format should have this content
```
GF_SECURITY_ADMIN_USER=admin
GF_SECURITY_ADMIN_PASSWORD=changeme
GF_USERS_ALLOW_SIGN_UP=false
```
If you want to change the password, you have to remove this entry, otherwise the change will not take effect
```
- grafana_data:/var/lib/grafana
```

Grafana is preconfigured with dashboards and Prometheus as the default data source:

* Name: Prometheus
* Type: Prometheus
* Url: http://prometheus:9090
* Access: proxy

***Docker Host Dashboard***

![Host](https://raw.githubusercontent.com/stefanprodan/dockprom/master/screens/Grafana_Docker_Host.png)

The Docker Host Dashboard shows key metrics for monitoring the resource usage of your server:

* Server uptime, CPU idle percent, number of CPU cores, available memory, swap and storage
* System load average graph, running and blocked by IO processes graph, interrupts graph
* CPU usage graph by mode (guest, idle, iowait, irq, nice, softirq, steal, system, user)
* Memory usage graph by distribution (used, free, buffers, cached)
* IO usage graph (read Bps, read Bps and IO time)
* Network usage graph by device (inbound Bps, Outbound Bps)
* Swap usage and activity graphs

For storage and particularly Free Storage graph, you have to specify the fstype in grafana graph request.
You can find it in `grafana/dashboards/docker_host.json`, at line 480 :

      "expr": "sum(node_filesystem_free_bytes{fstype=\"btrfs\"})",

I work on BTRFS, so i need to change `aufs` to `btrfs`.

You can find right value for your system in Prometheus `http://<host-ip>:9090` launching this request :

      node_filesystem_free_bytes

***Docker Containers Dashboard***

![Containers](https://raw.githubusercontent.com/stefanprodan/dockprom/master/screens/Grafana_Docker_Containers.png)

The Docker Containers Dashboard shows key metrics for monitoring running containers:

* Total containers CPU load, memory and storage usage
* Running containers graph, system load graph, IO usage graph
* Container CPU usage graph
* Container memory usage graph
* Container cached memory usage graph
* Container network inbound usage graph
* Container network outbound usage graph

> [!NOTE]
> This dashboard doesn't show the containers that are part of the monitoring stack.

***Monitor Services Dashboard***

![Monitor Services](https://raw.githubusercontent.com/stefanprodan/dockprom/master/screens/Grafana_Prometheus.png)

The Monitor Services Dashboard shows key metrics for monitoring the containers that make up the monitoring stack:

* Prometheus container uptime, monitoring stack total memory usage, Prometheus local storage memory chunks and series
* Container CPU usage graph
* Container memory usage graph
* Prometheus chunks to persist and persistence urgency graphs
* Prometheus chunks ops and checkpoint duration graphs
* Prometheus samples ingested rate, target scrapes and scrape duration graphs
* Prometheus HTTP requests graph
* Prometheus alerts graph

## Define alerts

Three alert groups have been setup within the [alert.rules](https://github.com/stefanprodan/dockprom/blob/master/prometheus/alert.rules) configuration file:

* Monitoring services alerts [targets](https://github.com/stefanprodan/dockprom/blob/master/prometheus/alert.rules#L2-L11)
* Docker Host alerts [host](https://github.com/stefanprodan/dockprom/blob/master/prometheus/alert.rules#L13-L40)
* Docker Containers alerts [containers](https://github.com/stefanprodan/dockprom/blob/master/prometheus/alert.rules#L42-L69)

You can modify the alert rules and reload them by making a HTTP POST call to Prometheus:

```
curl -X POST http://admin:admin@<host-ip>:9090/-/reload
```

***Monitoring services alerts***

Trigger an alert if any of the monitoring targets (node-exporter and cAdvisor) are down for more than 30 seconds:

```yaml
- alert: monitor_service_down
    expr: up == 0
    for: 30s
    labels:
      severity: critical
    annotations:
      summary: "Monitor service non-operational"
      description: "Service {{ $labels.instance }} is down."
```

***Docker Host alerts***

Trigger an alert if the Docker host CPU is under high load for more than 30 seconds:

```yaml
- alert: high_cpu_load
    expr: node_load1 > 1.5
    for: 30s
    labels:
      severity: warning
    annotations:
      summary: "Server under high load"
      description: "Docker host is under high load, the avg load 1m is at {{ $value}}. Reported by instance {{ $labels.instance }} of job {{ $labels.job }}."
```

Modify the load threshold based on your CPU cores.

Trigger an alert if the Docker host memory is almost full:

```yaml
- alert: high_memory_load
    expr: (sum(node_memory_MemTotal_bytes) - sum(node_memory_MemFree_bytes + node_memory_Buffers_bytes + node_memory_Cached_bytes) ) / sum(node_memory_MemTotal_bytes) * 100 > 85
    for: 30s
    labels:
      severity: warning
    annotations:
      summary: "Server memory is almost full"
      description: "Docker host memory usage is {{ humanize $value}}%. Reported by instance {{ $labels.instance }} of job {{ $labels.job }}."
```

Trigger an alert if the Docker host storage is almost full:

```yaml
- alert: high_storage_load
    expr: (node_filesystem_size_bytes{fstype="aufs"} - node_filesystem_free_bytes{fstype="aufs"}) / node_filesystem_size_bytes{fstype="aufs"}  * 100 > 85
    for: 30s
    labels:
      severity: warning
    annotations:
      summary: "Server storage is almost full"
      description: "Docker host storage usage is {{ humanize $value}}%. Reported by instance {{ $labels.instance }} of job {{ $labels.job }}."
```

***Docker Containers alerts***

Trigger an alert if a container is down for more than 30 seconds:

```yaml
- alert: jenkins_down
    expr: absent(container_memory_usage_bytes{name="jenkins"})
    for: 30s
    labels:
      severity: critical
    annotations:
      summary: "Jenkins down"
      description: "Jenkins container is down for more than 30 seconds."
```

Trigger an alert if a container is using more than 10% of total CPU cores for more than 30 seconds:

```yaml
- alert: jenkins_high_cpu
    expr: sum(rate(container_cpu_usage_seconds_total{name="jenkins"}[1m])) / count(node_cpu_seconds_total{mode="system"}) * 100 > 10
    for: 30s
    labels:
      severity: warning
    annotations:
      summary: "Jenkins high CPU usage"
      description: "Jenkins CPU usage is {{ humanize $value}}%."
```

Trigger an alert if a container is using more than 1.2GB of RAM for more than 30 seconds:

```yaml
- alert: jenkins_high_memory
    expr: sum(container_memory_usage_bytes{name="jenkins"}) > 1200000000
    for: 30s
    labels:
      severity: warning
    annotations:
      summary: "Jenkins high memory usage"
      description: "Jenkins memory consumption is at {{ humanize $value}}."
```

## Setup alerting

The AlertManager service is responsible for handling alerts sent by Prometheus server.
AlertManager can send notifications via email, Pushover, Slack, HipChat or any other system that exposes a webhook interface.
A complete list of integrations can be found [here](https://prometheus.io/docs/alerting/configuration).

You can view and silence notifications by accessing `http://<host-ip>:9093`.

The notification receivers can be configured in [alertmanager/config.yml](https://github.com/stefanprodan/dockprom/blob/master/alertmanager/config.yml) file.

To receive alerts via Slack you need to make a custom integration by choose ***incoming web hooks*** in your Slack team app page.
You can find more details on setting up Slack integration [here](http://www.robustperception.io/using-slack-with-the-alertmanager/).

Copy the Slack Webhook URL into the ***api_url*** field and specify a Slack ***channel***.

```yaml
route:
    receiver: 'slack'

receivers:
    - name: 'slack'
      slack_configs:
          - send_resolved: true
            text: "{{ .CommonAnnotations.description }}"
            username: 'Prometheus'
            channel: '#<channel>'
            api_url: 'https://hooks.slack.com/services/<webhook-id>'
```

![Slack Notifications](https://raw.githubusercontent.com/stefanprodan/dockprom/master/screens/Slack_Notifications.png)

## Sending metrics to the Pushgateway

The [pushgateway](https://github.com/prometheus/pushgateway) is used to collect data from batch jobs or from services.

To push data, simply execute:

    echo "some_metric 3.14" | curl --data-binary @- http://user:password@localhost:9091/metrics/job/some_job

Please replace the `user:password` part with your user and password set in the initial configuration (default: `admin:admin`).

## Updating Grafana to v5.2.2

[In Grafana versions >= 5.1 the id of the grafana user has been changed](http://docs.grafana.org/installation/docker/#migration-from-a-previous-version-of-the-docker-container-to-5-1-or-later). Unfortunately this means that files created prior to 5.1 won’t have the correct permissions for later versions.

| Version |   User  | User ID |
|:-------:|:-------:|:-------:|
|  < 5.1  | grafana |   104   |
|  \>= 5.1 | grafana |   472   |

There are two possible solutions to this problem.
- Change ownership from 104 to 472
- Start the upgraded container as user 104

##### Specifying a user in docker-compose.yml

To change ownership of the files run your grafana container as root and modify the permissions.

First perform a `docker-compose down` then modify your docker-compose.yml to include the `user: root` option:

```
  grafana:
    image: grafana/grafana:5.2.2
    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
    user: root
    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
    labels:
      org.label-schema.group: "monitoring"
```

Perform a `docker-compose up -d` and then issue the following commands:

```
docker exec -it --user root grafana bash

# in the container you just started:
chown -R root:root /etc/grafana && \
chmod -R a+r /etc/grafana && \
chown -R grafana:grafana /var/lib/grafana && \
chown -R grafana:grafana /usr/share/grafana
```

To run the grafana container as `user: 104` change your `docker-compose.yml` like such:

```
  grafana:
    image: grafana/grafana:5.2.2
    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
    user: "104"
    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
    labels:
      org.label-schema.group: "monitoring"
```
