# docker

## Setup

``` bash
curl -fsSL https://get.docker.com -o get-docker.sh
sh get-docker.sh
docker run hello-world
```

### Alphine
source https://wiki.alpinelinux.org/wiki/Docker

```bash
apk add docker
addgroup username docker
rc-update add docker default
service docker start
```
### fuse overlay

```bash
apt install --yes fuse-overlayfs
```

## Containers

### Containers list

```bash
docker container list
```


### Interactive shell

```bash
#example with ubuntu
docker container run -it ubuntu /bin/bash
```
### Remove when finished

```bash
#example with ubuntu
docker container run -rm ubuntu
```
### Attach to a running container

```bash
#attach to stdout of container with name ubuntu
docker container run -a ubuntu
## connects to container with name ubuntu and attach to bash (interactive)
docker exec -it pm_wp_adminer /bin/bash
```

## Volumes

### Export / Backup

```bash
#export volumes (tar) from dbstore container into volume
docker run --rm --volumes-from dbstore -v $(pwd):/backup ubuntu tar cvf /backup/backup.tar /dbdata
```


### Import / Restores

```bash
#inports volumes (untar) into dbstore2
docker run --rm --volumes-from dbstore2 -v $(pwd):/backup ubuntu bash -c "cd /dbdata && tar xvf /backup/backup.tar --strip 1"
```


### NFS

Notes:


docker-compose.yaml

```yaml
volumes:
  volume00:
    driver: local
    driver_opts:
      type: ${VOLUME_TYPE}
      o: ${VOLUME_O}
      device: "${VOLUME_DEVICE}"
```

.env

```text
VOLUME_TYPE="nfs"

# DNS server ip, RW:read and write
VOLUME_O="addr=10.10.1.1,rw" 

# Folder on NFS Server
## Must exists on nfs server, or security errors when starting container 
VOLUME_DEVICE=":/export/docker-volumes/volume00" 
```

## Network

### Macvlan

#### Create

How to create a docker macvlan network

```bash
# run on host
docker network create -d macvlan --subnet=192.168.1.249/24 --gateway=192.168.1.1  -o parent=eth0 macvlan_network
```

#### Host comunication

if network required between host and docker container on a macvlan docker network

* Option 1 - Create another macvlan on host

  * Setup vars

    ```bash
    MACVLAN_NAME=macvlan_bridge
    HOST_ETHERNET_ADP=eth0
    NETWORK=192.168.1.0/24
    ```

  * Create mavclan adapter

    ```bash
    ip link add $MACVLAN_NAME link $HOST_ETHERNET_ADP type macvlan mode bridge  
    ip addr add $NETWORK dev $MACVLAN_NAME  
    ifconfig $MACVLAN_NAME up  
    ```

  * Add routing

    ```bash
    ip route add $CONTAINER_MAVLAN_IP dev $MACVLAN_NAME
    ```

  * Delete mavclan adapter

    ```bash
    ifconfig $MACVLAN_NAME down
    ip link del $MACVLAN_NAME 
    ```

  * Persisting macvlan configuration
   Example:
    * network: 192.168.1.0/24
    * macvlan name:: macvlan_bridge
    * macvlan static ip: 192.168.1.240/32
    * docker containers on macvlan networks:
      * 192.168.1.254
      * 192.168.1.253
      * 192.168.1.250
      * 192.168.1.248

    ```text
    # create/edit /etc/network/interfaces.d/macvlan_bridge
    iface macvlan_bridge inet manual
        pre-up ip link add macvlan_bridge link eth0 type macvlan mode bridge
        pre-up ip addr add 192.168.1.240/32 dev macvlan_bridge
        up ip link set macvlan_bridge up
        post-up ip route add 192.168.1.254 dev macvlan_bridge
        post-up ip route add 192.168.1.253 dev macvlan_bridge
        post-up ip route add 192.168.1.252 dev macvlan_bridge
        post-up ip route add 192.168.1.250 dev macvlan_bridge
        post-up ip route add 192.168.1.248 dev macvlan_bridge
    ```

## log

write to docker log buffer

``` bash
echo "Hello World!" >> /proc/1/fd/1
``` 

clear all docker logs

``` bash
truncate -s 0 /var/lib/docker/containers/*/*-json.log;
``` 

## delete all images

``` bash
docker rmi -f $(docker images -aq)
``` 

## delete all images

``` bash
docker volume rm $(docker volume ls -qf dangling=true)
```