**Docker** has an extremely straightforward syntax to restart one or more containers.

# Format
```
docker restart {Options} {Container Name}
```
| Name, Shorthand  | Description  |
| - | - |
| `- -all`, `-a`  | Show all containers  |
| `- -quiet`, `-q`  | Only display numeric IDs  | 

To check which containers are active and running, use `docker ps`. Then, either *restart a single container* or *restart all containers*.

# Restarting a single container
```
docker restart edpresso_container
```

# Restarting all containers
```plaintext
docker restart $(docker ps -a -q)
```

# Restart policy
**Docker** also lets the user set the restart policy upon exit or failure. Users can type `docker ps` to check if the restart policy is active; it will be shown as either `Up`, when the container is up and running, or `Restarting` when the container is in the restart state.

## Format
```
docker run --restart={Policy} {Container Name}
```

## Policies
| Policy  | Result  |
| - | - |
| **no**  | Do not automatically restart the container when it exits. This is the default.  |
| **on-failure[:max-retries]**  | Restart only if the container exits with a non-zero exit status. Optionally, limit the number of restart retries the Docker daemon attempts.  |
| **always**  | Always restart the container regardless of the exit status. |
| **unless-stopped**  | Always restart the container regardless of the exit status, including on daemon startup, except if the container was put into a stopped state before the Docker daemon was stopped.  |

## Examples
### unless-stopped:
```
docker run --restart=unless-stopped edpresso_container
```

### on-failure:
```
docker run --restart=on-failure:15 edpresso_container
```

> Note: When restarting, an increasing delay is added after each restart. This delay starts from 100ms and doubles at every restart until the on-failure limit is reached or the docker container is stopped explicitly. This is done to avoid overflooding the server.


For analytics purposes, the user can `inspect` how many times the container has restarted: 
```
docker inspect -f "{{ .RestartCount }}" edpresso_container
```
Or the last time the container restarted:
```
docker inspect -f "{{ .State.StartedAt }}" edpresso_container
```

Name, Shorthand	Description
`- -all`, `-a`	Show all containers
`- -quiet`, `-q`	Only display numeric IDs

Policy	Result
no	Do not automatically restart the container when it exits. This is the default.
on-failure[:max-retries]	Restart only if the container exits with a non-zero exit status. Optionally, limit the number of restart retries the Docker daemon attempts.
always	Always restart the container regardless of the exit status.
unless-stopped	Always restart the container regardless of the exit status, including on daemon startup, except if the container was put into a stopped state before the Docker daemon was stopped.

Docker restart

Format

Restarting a single container

Restarting all containers

Restart policy

Format

Policies

Examples

unless-stopped:

on-failure: