add doc for live-restore setting and daemonless containers, fix admin guide menu
Signed-off-by: Charles Smith <charles.smith@docker.com>
This commit is contained in:
Charles Smith
parent
aeea20f51e
commit
cbd07495a3
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@ -6,7 +6,7 @@ description = "Using the Ambassador pattern to abstract (network) services"
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keywords = ["Examples, Usage, links, docker, documentation, examples, names, name, container naming"]
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[menu.main]
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parent = "engine_admin"
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weight = 6
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weight = 15
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+++
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<![end-metadata]-->
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@ -6,6 +6,7 @@ description = "Installation and using Docker via Chef"
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keywords = ["chef, installation, usage, docker, documentation"]
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[menu.main]
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parent = "engine_admin"
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weight="11"
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+++
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<![end-metadata]-->
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@ -1,293 +0,0 @@
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<!--[metadata]>
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+++
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aliases = ["/engine/articles/configuring/"]
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title = "Configuring and running Docker"
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description = "Configuring and running the Docker daemon on various distributions"
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keywords = ["docker, daemon, configuration, running, process managers"]
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[menu.main]
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parent = "engine_admin"
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weight = 3
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+++
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<![end-metadata]-->
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# Configuring and running Docker on various distributions
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After successfully installing Docker, the `docker` daemon runs with its default
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configuration.
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In a production environment, system administrators typically configure the
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`docker` daemon to start and stop according to an organization's requirements. In most
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cases, the system administrator configures a process manager such as `SysVinit`, `Upstart`,
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or `systemd` to manage the `docker` daemon's start and stop.
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### Running the docker daemon directly
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The `docker` daemon can be run directly using the `dockerd` command. By default it listens on
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the Unix socket `unix:///var/run/docker.sock`
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$ dockerd
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INFO[0000] +job init_networkdriver()
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INFO[0000] +job serveapi(unix:///var/run/docker.sock)
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INFO[0000] Listening for HTTP on unix (/var/run/docker.sock)
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...
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...
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### Configuring the docker daemon directly
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If you're running the `docker` daemon directly by running `docker daemon` instead
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of using a process manager, you can append the configuration options to the `docker` run
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command directly. Other options can be passed to the `docker` daemon to configure it.
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Some of the daemon's options are:
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| Flag | Description |
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|-----------------------|-----------------------------------------------------------|
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| `-D`, `--debug=false` | Enable or disable debug mode. By default, this is false. |
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| `-H`,`--host=[]` | Daemon socket(s) to connect to. |
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| `--tls=false` | Enable or disable TLS. By default, this is false. |
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Here is an example of running the `docker` daemon with configuration options:
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$ dockerd -D --tls=true --tlscert=/var/docker/server.pem --tlskey=/var/docker/serverkey.pem -H tcp://192.168.59.3:2376
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These options :
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- Enable `-D` (debug) mode
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- Set `tls` to true with the server certificate and key specified using `--tlscert` and `--tlskey` respectively
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- Listen for connections on `tcp://192.168.59.3:2376`
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The command line reference has the [complete list of daemon flags](../reference/commandline/dockerd.md)
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with explanations.
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### Daemon debugging
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As noted above, setting the log level of the daemon to "debug" or enabling debug mode
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with `-D` allows the administrator or operator to gain much more knowledge about the
|
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runtime activity of the daemon. If faced with a non-responsive daemon, the administrator
|
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can force a full stack trace of all threads to be added to the daemon log by sending the
|
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`SIGUSR1` signal to the Docker daemon. A common way to send this signal is using the `kill`
|
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command on Linux systems. For example, `kill -USR1 <daemon-pid>` sends the `SIGUSR1`
|
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signal to the daemon process, causing the stack dump to be added to the daemon log.
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> **Note:** The log level setting of the daemon must be at least "info" level and above for
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> the stack trace to be saved to the logfile. By default the daemon's log level is set to
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> "info".
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The daemon will continue operating after handling the `SIGUSR1` signal and dumping the stack
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traces to the log. The stack traces can be used to determine the state of all goroutines and
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threads within the daemon.
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## Ubuntu
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As of `14.04`, Ubuntu uses Upstart as a process manager. By default, Upstart jobs
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are located in `/etc/init` and the `docker` Upstart job can be found at `/etc/init/docker.conf`.
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After successfully [installing Docker for Ubuntu](../installation/linux/ubuntulinux.md),
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you can check the running status using Upstart in this way:
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$ sudo status docker
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docker start/running, process 989
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### Running Docker
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You can start/stop/restart the `docker` daemon using
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$ sudo start docker
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$ sudo stop docker
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$ sudo restart docker
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### Configuring Docker
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The instructions below depict configuring Docker on a system that uses `upstart`
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as the process manager. As of Ubuntu 15.04, Ubuntu uses `systemd` as its process
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manager. For Ubuntu 15.04 and higher, refer to [control and configure Docker with systemd](systemd.md).
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You configure the `docker` daemon in the `/etc/default/docker` file on your
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system. You do this by specifying values in a `DOCKER_OPTS` variable.
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To configure Docker options:
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1. Log into your host as a user with `sudo` or `root` privileges.
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2. If you don't have one, create the `/etc/default/docker` file on your host. Depending on how
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you installed Docker, you may already have this file.
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3. Open the file with your favorite editor.
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```
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$ sudo vi /etc/default/docker
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```
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4. Add a `DOCKER_OPTS` variable with the following options. These options are appended to the
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`docker` daemon's run command.
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```
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DOCKER_OPTS="-D --tls=true --tlscert=/var/docker/server.pem --tlskey=/var/docker/serverkey.pem -H tcp://192.168.59.3:2376"
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```
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These options :
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- Enable `-D` (debug) mode
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- Set `tls` to true with the server certificate and key specified using `--tlscert` and `--tlskey` respectively
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- Listen for connections on `tcp://192.168.59.3:2376`
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The command line reference has the [complete list of daemon flags](../reference/commandline/dockerd.md)
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with explanations.
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5. Save and close the file.
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6. Restart the `docker` daemon.
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```
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$ sudo restart docker
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```
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7. Verify that the `docker` daemon is running as specified with the `ps` command.
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```
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$ ps aux | grep docker | grep -v grep
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```
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### Logs
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By default logs for Upstart jobs are located in `/var/log/upstart` and the logs for `docker` daemon
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can be located at `/var/log/upstart/docker.log`
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$ tail -f /var/log/upstart/docker.log
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INFO[0000] Loading containers: done.
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INFO[0000] Docker daemon commit=1b09a95-unsupported graphdriver=aufs version=1.11.0-dev
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INFO[0000] +job acceptconnections()
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INFO[0000] -job acceptconnections() = OK (0)
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INFO[0000] Daemon has completed initialization
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## CentOS / Red Hat Enterprise Linux / Fedora
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As of `7.x`, CentOS and RHEL use `systemd` as the process manager. As of `21`, Fedora uses
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`systemd` as its process manager.
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After successfully installing Docker for [CentOS](../installation/linux/centos.md)/[Red Hat Enterprise Linux](../installation/linux/rhel.md)/[Fedora](../installation/linux/fedora.md), you can check the running status in this way:
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$ sudo systemctl status docker
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### Running Docker
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You can start/stop/restart the `docker` daemon using
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$ sudo systemctl start docker
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$ sudo systemctl stop docker
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$ sudo systemctl restart docker
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If you want Docker to start at boot, you should also:
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$ sudo systemctl enable docker
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### Configuring Docker
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For CentOS 7.x and RHEL 7.x you can [control and configure Docker with systemd](systemd.md).
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Previously, for CentOS 6.x and RHEL 6.x you would configure the `docker` daemon in
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the `/etc/sysconfig/docker` file on your system. You would do this by specifying
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values in a `other_args` variable. For a short time in CentOS 7.x and RHEL 7.x you
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would specify values in a `OPTIONS` variable. This is no longer recommended in favor
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of using systemd directly.
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For this section, we will use CentOS 7.x as an example to configure the `docker` daemon.
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To configure Docker options:
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1. Log into your host as a user with `sudo` or `root` privileges.
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2. Create the `/etc/systemd/system/docker.service.d` directory.
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```
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$ sudo mkdir /etc/systemd/system/docker.service.d
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```
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3. Create a `/etc/systemd/system/docker.service.d/docker.conf` file.
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4. Open the file with your favorite editor.
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```
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$ sudo vi /etc/systemd/system/docker.service.d/docker.conf
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```
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5. Override the `ExecStart` configuration from your `docker.service` file to customize
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the `docker` daemon. To modify the `ExecStart` configuration you have to specify
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an empty configuration followed by a new one as follows:
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```
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[Service]
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ExecStart=
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ExecStart=/usr/bin/dockerd -H fd:// -D --tls=true --tlscert=/var/docker/server.pem --tlskey=/var/docker/serverkey.pem -H tcp://192.168.59.3:2376
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```
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|
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These options :
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|
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- Enable `-D` (debug) mode
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- Set `tls` to true with the server certificate and key specified using `--tlscert` and `--tlskey` respectively
|
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- Listen for connections on `tcp://192.168.59.3:2376`
|
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|
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The command line reference has the [complete list of daemon flags](../reference/commandline/dockerd.md)
|
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with explanations.
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6. Save and close the file.
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7. Flush changes.
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```
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$ sudo systemctl daemon-reload
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```
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8. Restart the `docker` daemon.
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```
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$ sudo systemctl restart docker
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```
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9. Verify that the `docker` daemon is running as specified with the `ps` command.
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|
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```
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$ ps aux | grep docker | grep -v grep
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```
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### Logs
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systemd has its own logging system called the journal. The logs for the `docker` daemon can
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be viewed using `journalctl -u docker`
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$ sudo journalctl -u docker
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May 06 00:22:05 localhost.localdomain systemd[1]: Starting Docker Application Container Engine...
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May 06 00:22:05 localhost.localdomain docker[2495]: time="2015-05-06T00:22:05Z" level="info" msg="+job serveapi(unix:///var/run/docker.sock)"
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May 06 00:22:05 localhost.localdomain docker[2495]: time="2015-05-06T00:22:05Z" level="info" msg="Listening for HTTP on unix (/var/run/docker.sock)"
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May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="+job init_networkdriver()"
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May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="-job init_networkdriver() = OK (0)"
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May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="Loading containers: start."
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May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="Loading containers: done."
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May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="Docker daemon commit=1b09a95-unsupported graphdriver=aufs version=1.11.0-dev"
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May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="+job acceptconnections()"
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May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="-job acceptconnections() = OK (0)"
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_Note: Using and configuring journal is an advanced topic and is beyond the scope of this article._
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### Daemonless Containers
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Starting with Docker 1.12 containers can run without Docker or containerd running. This allows the
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Docker daemon to exit, be upgraded, or recover from a crash without affecting running containers
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on the system. To enable this functionality you need to add the `--live-restore` flag when
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launching `dockerd`. This will ensure that Docker does not kill containers on graceful shutdown or
|
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on restart leaving the containers running.
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While the Docker daemon is down logging will still be captured, however, it will be capped at the kernel's pipe buffer size before the buffer fills up, blocking the process.
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Docker will need to be restarted to flush these buffers.
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You can modify the kernel's buffer size by changing `/proc/sys/fs/pipe-max-size`.
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|
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@ -6,6 +6,7 @@ description = "Using DSC to configure a new Docker host"
|
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keywords = ["powershell, dsc, installation, usage, docker, documentation"]
|
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[menu.main]
|
||||
parent = "engine_admin"
|
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weight="10"
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
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|
|
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|||
|
|
@ -5,7 +5,7 @@ description = "CLI and log output formatting reference"
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keywords = ["format, formatting, output, templates, log"]
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[menu.main]
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parent = "engine_admin"
|
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weight=-90
|
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weight=7
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+++
|
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<![end-metadata]-->
|
||||
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|
|
|
|||
|
|
@ -6,6 +6,7 @@ description = "How to generate scripts for upstart, systemd, etc."
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keywords = ["systemd, upstart, supervisor, docker, documentation, host integration"]
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[menu.main]
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||||
parent = "engine_admin"
|
||||
weight="5"
|
||||
+++
|
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<![end-metadata]-->
|
||||
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|
|
|
|||
|
|
@ -1,11 +1,283 @@
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<!-- [metadata]>
|
||||
<!--[metadata]>
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+++
|
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title = "Administrate"
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description = "Administrate"
|
||||
keywords = ["Administrate"]
|
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aliases = [
|
||||
"/engine/articles/configuring/",
|
||||
"/engine/admin/configuring/"
|
||||
]
|
||||
title = "Configuring and running Docker"
|
||||
description = "Configuring and running the Docker daemon on various distributions"
|
||||
keywords = ["docker, daemon, configuration, running, process managers"]
|
||||
[menu.main]
|
||||
parent="engine_use"
|
||||
identifier="engine_admin"
|
||||
weight="-70"
|
||||
parent = "engine_admin"
|
||||
weight = 0
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
|
||||
# Configuring and running Docker on various distributions
|
||||
|
||||
After successfully installing Docker, the `docker` daemon runs with its default
|
||||
configuration.
|
||||
|
||||
In a production environment, system administrators typically configure the
|
||||
`docker` daemon to start and stop according to an organization's requirements. In most
|
||||
cases, the system administrator configures a process manager such as `SysVinit`, `Upstart`,
|
||||
or `systemd` to manage the `docker` daemon's start and stop.
|
||||
|
||||
### Running the docker daemon directly
|
||||
|
||||
The `docker` daemon can be run directly using the `dockerd` command. By default it listens on
|
||||
the Unix socket `unix:///var/run/docker.sock`
|
||||
|
||||
$ dockerd
|
||||
|
||||
INFO[0000] +job init_networkdriver()
|
||||
INFO[0000] +job serveapi(unix:///var/run/docker.sock)
|
||||
INFO[0000] Listening for HTTP on unix (/var/run/docker.sock)
|
||||
...
|
||||
...
|
||||
|
||||
### Configuring the docker daemon directly
|
||||
|
||||
If you're running the `docker` daemon directly by running `docker daemon` instead
|
||||
of using a process manager, you can append the configuration options to the `docker` run
|
||||
command directly. Other options can be passed to the `docker` daemon to configure it.
|
||||
|
||||
Some of the daemon's options are:
|
||||
|
||||
| Flag | Description |
|
||||
|-----------------------|-----------------------------------------------------------|
|
||||
| `-D`, `--debug=false` | Enable or disable debug mode. By default, this is false. |
|
||||
| `-H`,`--host=[]` | Daemon socket(s) to connect to. |
|
||||
| `--tls=false` | Enable or disable TLS. By default, this is false. |
|
||||
|
||||
|
||||
Here is an example of running the `docker` daemon with configuration options:
|
||||
|
||||
$ dockerd -D --tls=true --tlscert=/var/docker/server.pem --tlskey=/var/docker/serverkey.pem -H tcp://192.168.59.3:2376
|
||||
|
||||
These options :
|
||||
|
||||
- Enable `-D` (debug) mode
|
||||
- Set `tls` to true with the server certificate and key specified using `--tlscert` and `--tlskey` respectively
|
||||
- Listen for connections on `tcp://192.168.59.3:2376`
|
||||
|
||||
The command line reference has the [complete list of daemon flags](../reference/commandline/dockerd.md)
|
||||
with explanations.
|
||||
|
||||
### Daemon debugging
|
||||
|
||||
As noted above, setting the log level of the daemon to "debug" or enabling debug mode
|
||||
with `-D` allows the administrator or operator to gain much more knowledge about the
|
||||
runtime activity of the daemon. If faced with a non-responsive daemon, the administrator
|
||||
can force a full stack trace of all threads to be added to the daemon log by sending the
|
||||
`SIGUSR1` signal to the Docker daemon. A common way to send this signal is using the `kill`
|
||||
command on Linux systems. For example, `kill -USR1 <daemon-pid>` sends the `SIGUSR1`
|
||||
signal to the daemon process, causing the stack dump to be added to the daemon log.
|
||||
|
||||
> **Note:** The log level setting of the daemon must be at least "info" level and above for
|
||||
> the stack trace to be saved to the logfile. By default the daemon's log level is set to
|
||||
> "info".
|
||||
|
||||
The daemon will continue operating after handling the `SIGUSR1` signal and dumping the stack
|
||||
traces to the log. The stack traces can be used to determine the state of all goroutines and
|
||||
threads within the daemon.
|
||||
|
||||
## Ubuntu
|
||||
|
||||
As of `14.04`, Ubuntu uses Upstart as a process manager. By default, Upstart jobs
|
||||
are located in `/etc/init` and the `docker` Upstart job can be found at `/etc/init/docker.conf`.
|
||||
|
||||
After successfully [installing Docker for Ubuntu](../installation/linux/ubuntulinux.md),
|
||||
you can check the running status using Upstart in this way:
|
||||
|
||||
$ sudo status docker
|
||||
|
||||
docker start/running, process 989
|
||||
|
||||
### Running Docker
|
||||
|
||||
You can start/stop/restart the `docker` daemon using
|
||||
|
||||
$ sudo start docker
|
||||
|
||||
$ sudo stop docker
|
||||
|
||||
$ sudo restart docker
|
||||
|
||||
|
||||
### Configuring Docker
|
||||
|
||||
The instructions below depict configuring Docker on a system that uses `upstart`
|
||||
as the process manager. As of Ubuntu 15.04, Ubuntu uses `systemd` as its process
|
||||
manager. For Ubuntu 15.04 and higher, refer to [control and configure Docker with systemd](systemd.md).
|
||||
|
||||
You configure the `docker` daemon in the `/etc/default/docker` file on your
|
||||
system. You do this by specifying values in a `DOCKER_OPTS` variable.
|
||||
|
||||
To configure Docker options:
|
||||
|
||||
1. Log into your host as a user with `sudo` or `root` privileges.
|
||||
|
||||
2. If you don't have one, create the `/etc/default/docker` file on your host. Depending on how
|
||||
you installed Docker, you may already have this file.
|
||||
|
||||
3. Open the file with your favorite editor.
|
||||
|
||||
```
|
||||
$ sudo vi /etc/default/docker
|
||||
```
|
||||
|
||||
4. Add a `DOCKER_OPTS` variable with the following options. These options are appended to the
|
||||
`docker` daemon's run command.
|
||||
|
||||
```
|
||||
DOCKER_OPTS="-D --tls=true --tlscert=/var/docker/server.pem --tlskey=/var/docker/serverkey.pem -H tcp://192.168.59.3:2376"
|
||||
```
|
||||
|
||||
These options :
|
||||
|
||||
- Enable `-D` (debug) mode
|
||||
- Set `tls` to true with the server certificate and key specified using `--tlscert` and `--tlskey` respectively
|
||||
- Listen for connections on `tcp://192.168.59.3:2376`
|
||||
|
||||
The command line reference has the [complete list of daemon flags](../reference/commandline/dockerd.md)
|
||||
with explanations.
|
||||
|
||||
|
||||
5. Save and close the file.
|
||||
|
||||
6. Restart the `docker` daemon.
|
||||
|
||||
```
|
||||
$ sudo restart docker
|
||||
```
|
||||
|
||||
7. Verify that the `docker` daemon is running as specified with the `ps` command.
|
||||
|
||||
```
|
||||
$ ps aux | grep docker | grep -v grep
|
||||
```
|
||||
|
||||
### Logs
|
||||
|
||||
By default logs for Upstart jobs are located in `/var/log/upstart` and the logs for `docker` daemon
|
||||
can be located at `/var/log/upstart/docker.log`
|
||||
|
||||
$ tail -f /var/log/upstart/docker.log
|
||||
INFO[0000] Loading containers: done.
|
||||
INFO[0000] Docker daemon commit=1b09a95-unsupported graphdriver=aufs version=1.11.0-dev
|
||||
INFO[0000] +job acceptconnections()
|
||||
INFO[0000] -job acceptconnections() = OK (0)
|
||||
INFO[0000] Daemon has completed initialization
|
||||
|
||||
|
||||
## CentOS / Red Hat Enterprise Linux / Fedora
|
||||
|
||||
As of `7.x`, CentOS and RHEL use `systemd` as the process manager. As of `21`, Fedora uses
|
||||
`systemd` as its process manager.
|
||||
|
||||
After successfully installing Docker for [CentOS](../installation/linux/centos.md)/[Red Hat Enterprise Linux](../installation/linux/rhel.md)/[Fedora](../installation/linux/fedora.md), you can check the running status in this way:
|
||||
|
||||
$ sudo systemctl status docker
|
||||
|
||||
### Running Docker
|
||||
|
||||
You can start/stop/restart the `docker` daemon using
|
||||
|
||||
$ sudo systemctl start docker
|
||||
|
||||
$ sudo systemctl stop docker
|
||||
|
||||
$ sudo systemctl restart docker
|
||||
|
||||
If you want Docker to start at boot, you should also:
|
||||
|
||||
$ sudo systemctl enable docker
|
||||
|
||||
### Configuring Docker
|
||||
|
||||
For CentOS 7.x and RHEL 7.x you can [control and configure Docker with systemd](systemd.md).
|
||||
|
||||
Previously, for CentOS 6.x and RHEL 6.x you would configure the `docker` daemon in
|
||||
the `/etc/sysconfig/docker` file on your system. You would do this by specifying
|
||||
values in a `other_args` variable. For a short time in CentOS 7.x and RHEL 7.x you
|
||||
would specify values in a `OPTIONS` variable. This is no longer recommended in favor
|
||||
of using systemd directly.
|
||||
|
||||
For this section, we will use CentOS 7.x as an example to configure the `docker` daemon.
|
||||
|
||||
To configure Docker options:
|
||||
|
||||
1. Log into your host as a user with `sudo` or `root` privileges.
|
||||
|
||||
2. Create the `/etc/systemd/system/docker.service.d` directory.
|
||||
|
||||
```
|
||||
$ sudo mkdir /etc/systemd/system/docker.service.d
|
||||
```
|
||||
|
||||
3. Create a `/etc/systemd/system/docker.service.d/docker.conf` file.
|
||||
|
||||
4. Open the file with your favorite editor.
|
||||
|
||||
```
|
||||
$ sudo vi /etc/systemd/system/docker.service.d/docker.conf
|
||||
```
|
||||
|
||||
5. Override the `ExecStart` configuration from your `docker.service` file to customize
|
||||
the `docker` daemon. To modify the `ExecStart` configuration you have to specify
|
||||
an empty configuration followed by a new one as follows:
|
||||
|
||||
```
|
||||
[Service]
|
||||
ExecStart=
|
||||
ExecStart=/usr/bin/dockerd -H fd:// -D --tls=true --tlscert=/var/docker/server.pem --tlskey=/var/docker/serverkey.pem -H tcp://192.168.59.3:2376
|
||||
```
|
||||
|
||||
These options :
|
||||
|
||||
- Enable `-D` (debug) mode
|
||||
- Set `tls` to true with the server certificate and key specified using `--tlscert` and `--tlskey` respectively
|
||||
- Listen for connections on `tcp://192.168.59.3:2376`
|
||||
|
||||
The command line reference has the [complete list of daemon flags](../reference/commandline/dockerd.md)
|
||||
with explanations.
|
||||
|
||||
6. Save and close the file.
|
||||
|
||||
7. Flush changes.
|
||||
|
||||
```
|
||||
$ sudo systemctl daemon-reload
|
||||
```
|
||||
|
||||
8. Restart the `docker` daemon.
|
||||
|
||||
```
|
||||
$ sudo systemctl restart docker
|
||||
```
|
||||
|
||||
9. Verify that the `docker` daemon is running as specified with the `ps` command.
|
||||
|
||||
```
|
||||
$ ps aux | grep docker | grep -v grep
|
||||
```
|
||||
|
||||
### Logs
|
||||
|
||||
systemd has its own logging system called the journal. The logs for the `docker` daemon can
|
||||
be viewed using `journalctl -u docker`
|
||||
|
||||
$ sudo journalctl -u docker
|
||||
May 06 00:22:05 localhost.localdomain systemd[1]: Starting Docker Application Container Engine...
|
||||
May 06 00:22:05 localhost.localdomain docker[2495]: time="2015-05-06T00:22:05Z" level="info" msg="+job serveapi(unix:///var/run/docker.sock)"
|
||||
May 06 00:22:05 localhost.localdomain docker[2495]: time="2015-05-06T00:22:05Z" level="info" msg="Listening for HTTP on unix (/var/run/docker.sock)"
|
||||
May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="+job init_networkdriver()"
|
||||
May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="-job init_networkdriver() = OK (0)"
|
||||
May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="Loading containers: start."
|
||||
May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="Loading containers: done."
|
||||
May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="Docker daemon commit=1b09a95-unsupported graphdriver=aufs version=1.11.0-dev"
|
||||
May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="+job acceptconnections()"
|
||||
May 06 00:22:06 localhost.localdomain docker[2495]: time="2015-05-06T00:22:06Z" level="info" msg="-job acceptconnections() = OK (0)"
|
||||
|
||||
_Note: Using and configuring journal is an advanced topic and is beyond the scope of this article._
|
||||
|
|
|
|||
|
|
@ -0,0 +1,80 @@
|
|||
<!--[metadata]>
|
||||
+++
|
||||
title = "Keep containers alive during daemon downtime"
|
||||
description = "How to keep containers running when the daemon isn't available."
|
||||
keywords = ["docker, upgrade, daemon, dockerd, live-restore, daemonless container"]
|
||||
[menu.main]
|
||||
parent = "engine_admin"
|
||||
weight="6"
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
|
||||
# Keep containers alive during daemon downtime
|
||||
|
||||
By default, when the Docker daemon terminates, it shuts down running containers.
|
||||
Starting with Docker Engine 1.12, you can configure the daemon so that containers remain
|
||||
running if the daemon becomes unavailable. The live restore option helps reduce
|
||||
container downtime due to daemon crashes, planned outages, or upgrades.
|
||||
|
||||
## Enable the live restore option
|
||||
|
||||
There are two ways to enable the live restore setting to keep containers alive
|
||||
when the daemon becomes unavailable:
|
||||
|
||||
* If the daemon is already running and you don't want to stop it, you can add
|
||||
the configuration to the daemon configuration file. For example, on a linux
|
||||
system the default configuration file is `/etc/docker/daemon.json`.
|
||||
|
||||
Use your favorite editor to enable the `live-restore` option in the
|
||||
`daemon.json`.
|
||||
|
||||
```bash
|
||||
{
|
||||
"live-restore": true
|
||||
}
|
||||
```
|
||||
|
||||
You have to send a `SIGHUP` signal to the daemon process for it to reload the
|
||||
configuration. For more information on how to configure the Docker daemon using
|
||||
config.json, see [daemon configuration file](../reference/commandline/dockerd.md#daemon-configuration-file)
|
||||
|
||||
* When you start the Docker daemon, pass the `--live-restore` flag:
|
||||
|
||||
```bash
|
||||
$ sudo dockerd --live-restore
|
||||
```
|
||||
|
||||
## Live restore during upgrades
|
||||
|
||||
The live restore feature supports restoring containers to the daemon for
|
||||
upgrades from one minor release to the next. For example from Docker Engine
|
||||
1.12.1 to 1.13.2.
|
||||
|
||||
If you skip releases during an upgrade, the daemon may not restore connection
|
||||
the containers. If the daemon is unable restore connection, it ignores the
|
||||
running containers and you must manage them manually. The daemon won't shut down
|
||||
the disconnected containers.
|
||||
|
||||
## Live restore upon restart
|
||||
|
||||
The live restore option only works to restore the same set of daemon options
|
||||
as the daemon had before it stopped. For example, live restore may not work if
|
||||
the daemon restarts with a different bridge IP or a different graphdriver.
|
||||
|
||||
## Impact of live restore on running containers
|
||||
|
||||
A lengthy absence of the daemon can impact running containers. The containers
|
||||
process writes to FIFO logs for daemon consumption. If the daemon is unavailable
|
||||
to consume the output, the buffer will fill up and block further writes to the
|
||||
log. A full log blocks the process until further space is available. The default
|
||||
buffer size is typically 64K.
|
||||
|
||||
You must restart Docker to flush the buffers.
|
||||
|
||||
You can modify the kernel's buffer size by changing `/proc/sys/fs/pipe-max-size`.
|
||||
|
||||
## Live restore and swarm mode
|
||||
|
||||
The live restore option is not compatible with Docker Engine swarm mode. When
|
||||
the Docker Engine runs in swarm mode, the orchestration feature manages tasks
|
||||
and keeps containers running according to a service specification.
|
||||
|
|
@ -7,7 +7,7 @@ keywords = [" docker, logging, driver"]
|
|||
[menu.main]
|
||||
parent = "engine_admin"
|
||||
identifier = "smn_logging"
|
||||
weight=8
|
||||
weight=9
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
|
||||
|
|
|
|||
|
|
@ -0,0 +1,27 @@
|
|||
<!-- [metadata]>
|
||||
+++
|
||||
title = "Admin Guide"
|
||||
description = "Administer Docker"
|
||||
keywords = ["Administer"]
|
||||
type="menu"
|
||||
[menu.main]
|
||||
parent="engine_use"
|
||||
identifier="engine_admin"
|
||||
weight="-70"
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
|
||||
# Admin Topics
|
||||
|
||||
* [Configuring and running Docker](index.md)
|
||||
* [Automatically start containers](host_integration.md)
|
||||
* [Keep containers alive during daemon downtime](live-restore.md)
|
||||
* [Control and configure Docker with systemd](systemd.md)
|
||||
* [Format command and log output](formatting.md)
|
||||
* [Run a local registry mirror](registry_mirror.md)
|
||||
* [PowerShell DSC Usage](dsc.md)
|
||||
* [Using Chef](chef.md)
|
||||
* [Using Puppet](puppet.md)
|
||||
* [Using Supervisor with Docker](using_supervisord.md)
|
||||
* [Runtime metrics](runmetrics.md)
|
||||
* [Link via an ambassador container](ambassador_pattern_linking.md)
|
||||
|
|
@ -6,6 +6,7 @@ description = "Installing and using Puppet"
|
|||
keywords = ["puppet, installation, usage, docker, documentation"]
|
||||
[menu.main]
|
||||
parent = "engine_admin"
|
||||
weight="12"
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
|
||||
|
|
|
|||
|
|
@ -6,7 +6,7 @@ description = "Measure the behavior of running containers"
|
|||
keywords = ["docker, metrics, CPU, memory, disk, IO, run, runtime, stats"]
|
||||
[menu.main]
|
||||
parent = "engine_admin"
|
||||
weight = 4
|
||||
weight = 14
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
|
||||
|
|
@ -139,7 +139,7 @@ indicates the number of page faults which happened since the creation of
|
|||
the cgroup; this number can never decrease).
|
||||
|
||||
|
||||
- **cache:**
|
||||
- **cache:**
|
||||
the amount of memory used by the processes of this control group
|
||||
that can be associated precisely with a block on a block device.
|
||||
When you read from and write to files on disk, this amount will
|
||||
|
|
@ -149,16 +149,16 @@ the cgroup; this number can never decrease).
|
|||
`mmap`). It also accounts for the memory used by
|
||||
`tmpfs` mounts, though the reasons are unclear.
|
||||
|
||||
- **rss:**
|
||||
- **rss:**
|
||||
the amount of memory that *doesn't* correspond to anything on disk:
|
||||
stacks, heaps, and anonymous memory maps.
|
||||
|
||||
- **mapped_file:**
|
||||
- **mapped_file:**
|
||||
indicates the amount of memory mapped by the processes in the
|
||||
control group. It doesn't give you information about *how much*
|
||||
memory is used; it rather tells you *how* it is used.
|
||||
|
||||
- **pgfault and pgmajfault:**
|
||||
- **pgfault and pgmajfault:**
|
||||
indicate the number of times that a process of the cgroup triggered
|
||||
a "page fault" and a "major fault", respectively. A page fault
|
||||
happens when a process accesses a part of its virtual memory space
|
||||
|
|
@ -177,10 +177,10 @@ the cgroup; this number can never decrease).
|
|||
it just has to duplicate an existing page, or allocate an empty
|
||||
page, it's a regular (or "minor") fault.
|
||||
|
||||
- **swap:**
|
||||
- **swap:**
|
||||
the amount of swap currently used by the processes in this cgroup.
|
||||
|
||||
- **active_anon and inactive_anon:**
|
||||
- **active_anon and inactive_anon:**
|
||||
the amount of *anonymous* memory that has been identified has
|
||||
respectively *active* and *inactive* by the kernel. "Anonymous"
|
||||
memory is the memory that is *not* linked to disk pages. In other
|
||||
|
|
@ -195,7 +195,7 @@ the cgroup; this number can never decrease).
|
|||
retagged "active". When the kernel is almost out of memory, and time
|
||||
comes to swap out to disk, the kernel will swap "inactive" pages.
|
||||
|
||||
- **active_file and inactive_file:**
|
||||
- **active_file and inactive_file:**
|
||||
cache memory, with *active* and *inactive* similar to the *anon*
|
||||
memory above. The exact formula is cache = **active_file** +
|
||||
**inactive_file** + **tmpfs**. The exact rules used by the kernel
|
||||
|
|
@ -206,14 +206,14 @@ the cgroup; this number can never decrease).
|
|||
since it can be reclaimed immediately (while anonymous pages and
|
||||
dirty/modified pages have to be written to disk first).
|
||||
|
||||
- **unevictable:**
|
||||
- **unevictable:**
|
||||
the amount of memory that cannot be reclaimed; generally, it will
|
||||
account for memory that has been "locked" with `mlock`.
|
||||
It is often used by crypto frameworks to make sure that
|
||||
secret keys and other sensitive material never gets swapped out to
|
||||
disk.
|
||||
|
||||
- **memory and memsw limits:**
|
||||
- **memory and memsw limits:**
|
||||
These are not really metrics, but a reminder of the limits applied
|
||||
to this cgroup. The first one indicates the maximum amount of
|
||||
physical memory that can be used by the processes of this control
|
||||
|
|
@ -261,21 +261,21 @@ file in the kernel documentation, here is a short list of the most
|
|||
relevant ones:
|
||||
|
||||
|
||||
- **blkio.sectors:**
|
||||
- **blkio.sectors:**
|
||||
contain the number of 512-bytes sectors read and written by the
|
||||
processes member of the cgroup, device by device. Reads and writes
|
||||
are merged in a single counter.
|
||||
|
||||
- **blkio.io_service_bytes:**
|
||||
- **blkio.io_service_bytes:**
|
||||
indicates the number of bytes read and written by the cgroup. It has
|
||||
4 counters per device, because for each device, it differentiates
|
||||
between synchronous vs. asynchronous I/O, and reads vs. writes.
|
||||
|
||||
- **blkio.io_serviced:**
|
||||
- **blkio.io_serviced:**
|
||||
the number of I/O operations performed, regardless of their size. It
|
||||
also has 4 counters per device.
|
||||
|
||||
- **blkio.io_queued:**
|
||||
- **blkio.io_queued:**
|
||||
indicates the number of I/O operations currently queued for this
|
||||
cgroup. In other words, if the cgroup isn't doing any I/O, this will
|
||||
be zero. Note that the opposite is not true. In other words, if
|
||||
|
|
|
|||
|
|
@ -6,6 +6,7 @@ description = "Controlling and configuring Docker using systemd"
|
|||
keywords = ["docker, daemon, systemd, configuration"]
|
||||
[menu.main]
|
||||
parent = "engine_admin"
|
||||
weight="7"
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
|
||||
|
|
|
|||
|
|
@ -6,6 +6,7 @@ description = "How to use Supervisor process management with Docker"
|
|||
keywords = ["docker, supervisor, process management"]
|
||||
[menu.main]
|
||||
parent = "engine_admin"
|
||||
weight="13"
|
||||
+++
|
||||
<![end-metadata]-->
|
||||
|
||||
|
|
|
|||
|
|
@ -56,7 +56,7 @@ Options:
|
|||
--ipv6 Enable IPv6 networking
|
||||
-l, --log-level=info Set the logging level
|
||||
--label=[] Set key=value labels to the daemon
|
||||
--live-restore Enable live restore of docker when containers are still running
|
||||
--live-restore Enables keeping containers alive during daemon downtime
|
||||
--log-driver=json-file Default driver for container logs
|
||||
--log-opt=map[] Default log driver options for containers
|
||||
--max-concurrent-downloads=3 Set the max concurrent downloads for each pull
|
||||
|
|
@ -1002,14 +1002,14 @@ via flags. The docker daemon fails to start if an option is duplicated between
|
|||
the file and the flags, regardless their value. We do this to avoid
|
||||
silently ignore changes introduced in configuration reloads.
|
||||
For example, the daemon fails to start if you set daemon labels
|
||||
in the configuration file and also set daemon labels via the `--label` flag.
|
||||
in the configuration file and also set daemon labels via the `--label` flag.
|
||||
Options that are not present in the file are ignored when the daemon starts.
|
||||
|
||||
### Linux configuration file
|
||||
|
||||
The default location of the configuration file on Linux is
|
||||
The default location of the configuration file on Linux is
|
||||
`/etc/docker/daemon.json`. The `--config-file` flag can be used to specify a
|
||||
non-default location.
|
||||
non-default location.
|
||||
|
||||
This is a full example of the allowed configuration options on Linux:
|
||||
|
||||
|
|
@ -1024,6 +1024,7 @@ This is a full example of the allowed configuration options on Linux:
|
|||
"storage-driver": "",
|
||||
"storage-opts": [],
|
||||
"labels": [],
|
||||
"live-restore": true,
|
||||
"log-driver": "",
|
||||
"log-opts": [],
|
||||
"mtu": 0,
|
||||
|
|
@ -1085,7 +1086,7 @@ This is a full example of the allowed configuration options on Linux:
|
|||
|
||||
The default location of the configuration file on Windows is
|
||||
`%programdata%\docker\config\daemon.json`. The `--config-file` flag can be
|
||||
used to specify a non-default location.
|
||||
used to specify a non-default location.
|
||||
|
||||
This is a full example of the allowed configuration options on Windows:
|
||||
|
||||
|
|
@ -1099,7 +1100,8 @@ This is a full example of the allowed configuration options on Windows:
|
|||
"storage-driver": "",
|
||||
"storage-opts": [],
|
||||
"labels": [],
|
||||
"log-driver": "",
|
||||
"live-restore": true,
|
||||
"log-driver": "",
|
||||
"mtu": 0,
|
||||
"pidfile": "",
|
||||
"graph": "",
|
||||
|
|
@ -1139,6 +1141,7 @@ The list of currently supported options that can be reconfigured is this:
|
|||
- `cluster-store-opts`: it uses the new options to reload the discovery store.
|
||||
- `cluster-advertise`: it modifies the address advertised after reloading.
|
||||
- `labels`: it replaces the daemon labels with a new set of labels.
|
||||
- `live-restore`: Enables [keeping containers alive during daemon downtime](../../admin/live-restore.md).
|
||||
- `max-concurrent-downloads`: it updates the max concurrent downloads for each pull.
|
||||
- `max-concurrent-uploads`: it updates the max concurrent uploads for each push.
|
||||
- `default-runtime`: it updates the runtime to be used if not is
|
||||
|
|
|
|||
Loading…
Reference in New Issue