Description Daniel Tröder 2023-06-09 08:23:28 CEST

Currently, two options for the logging driver (below the "log-opts" key) are hard-coded into /etc/docker/daemon.json. Those options are however not compatible with all logging drivers:

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# cat /etc/docker/daemon.json 
{
    "bip": "172.17.42.1/16",
    "live-restore": true,
    "log-driver": "json-file",
    "log-opts": {
        "max-file": "4",
        "max-size": "10m"
    }
}

# ucr set docker/daemon/default/opts/log-driver=journald
# cat /etc/docker/daemon.json 
{
    "bip": "172.17.42.1/16",
    "live-restore": true,
    "log-driver": "journald",
    "log-opts": {
        "max-file": "4",
        "max-size": "10m"
    }
}

# systemctl restart docker.service 
Job for docker.service failed because the control process exited with error code.
See "systemctl status docker.service" and "journalctl -xe" for details.

# grep max-file /var/log/syslog
Jun  9 08:02:40 self-disclosure1 dockerd[19391]: failed to start daemon: failed to set log opts: unknown log opt 'max-file' for journald log driver
Jun  9 08:02:42 self-disclosure1 dockerd[19404]: failed to start daemon: failed to set log opts: unknown log opt 'max-file' for journald log driver

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I wrote a patch for the UCR template that enables "log-opts" according to the documentation of each logging driver:


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# ucr set docker/daemon/default/opts/log-driver=json-file
# cat /etc/docker/daemon.json 
{
    "bip": "172.17.42.1/16",
    "live-restore": true,
    "log-driver": "json-file",
    "log-opts": {
        "env": "DOCKER_HOST_NAME",
        "labels": "APP_NAME,APP_VERSION,UCS",
        "max-file": "4",
        "max-size": "10m",
        "tag": "{{.ImageName}}/{{.Name}}/{{.ID}}"
    }
}

# systemctl restart docker.service && echo OK
OK

# ucr set docker/daemon/default/opts/log-driver=journald
# cat /etc/docker/daemon.json 
{
    "bip": "172.17.42.1/16",
    "live-restore": true,
    "log-driver": "journald",
    "log-opts": {
        "env": "DOCKER_HOST_NAME",
        "labels": "APP_NAME,APP_VERSION,UCS",
        "tag": "{{.ImageName}}/{{.Name}}/{{.ID}}"
    }
}

# systemctl restart docker.service && echo OK
OK

# ucr set docker/daemon/default/opts/log-driver=fluentd
# cat /etc/docker/daemon.json 
{
    "bip": "172.17.42.1/16",
    "live-restore": true,
    "log-driver": "fluentd",
    "log-opts": {
        "env": "DOCKER_HOST_NAME",
        "fluentd-address": "unix:///var/run/fluentd.sock",
        "fluentd-sub-second-precision": "true",
        "labels": "APP_NAME,APP_VERSION,UCS",
        "tag": "docker-logs"
    }
}

# systemctl restart docker.service && echo OK
OK


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The ["log-opts"]["labels"] configuration is meant to work with Bug <to-be-created>.