一个简单而伟大的解决方案是牧羊人

另一种方法是假设您的基本映像很快就会落后(这很可能发生)，并定期强制应用程序构建另一个映像(例如每周)，如果它发生了更改，则重新部署它。

据我所知，像官方Debian或Java这样的流行基础镜像会更新它们的标记来满足安全修复，所以标记不是不可变的(如果你想要更强的保证，你需要使用参考[image:@digest]，在最新的Docker版本中可用)。因此，如果你要用docker build -pull构建你的映像，那么你的应用程序应该得到你引用的base image标签的最新和最好的。

由于可变标记可能令人困惑，所以最好每次都增加应用程序的版本号，这样至少在您的方面，事情会更清楚。

因此，我不确定在前面的答案之一中建议的脚本是否能完成工作，因为它不重新构建应用程序的映像——它只是更新基本映像标记，然后重新启动容器，但新的容器仍然引用旧的基本映像散列。

我不提倡在容器中运行cron类型的作业(或任何其他进程，除非真的有必要)，因为这违背了每个容器只运行一个进程的原则(关于为什么这样更好有各种各样的争论，所以我不打算在这里讨论)。

以上答案也是正确的

有两种方法

使用的人 每隔一分钟运行脚本以获取新的docker映像

我只是分享脚本，可能会对你有帮助! 你可以用cronjob，我在OSX上成功尝试过

#!/bin/bash
##You can use below commented line for setting cron tab for running cron job and to store its O/P in one .txt file  
#* * * * * /usr/bin/sudo -u admin -i bash -c /Users/Swapnil/Documents/checkimg.sh > /Users/Swapnil/Documents/cron_output.log 2>&1
# Example for the Docker Hub V2 API
# Returns all images and tags associated with a Docker Hub organization account.
# Requires 'jq': https://stedolan.github.io/jq/

# set username, password, and organization
# Filepath where your docker-compose file is present
FILEPATH="/Users/Swapnil/Documents/lamp-alpine"
# Your Docker hub user name
UNAME="ur username"
# Your Docker hub user password
UPASS="ur pwd"
# e.g organisation_name/image_name:image_tag
ORG="ur org name"
IMGNAME="ur img name"
IMGTAG="ur img tag"
# Container name
CONTNAME="ur container name"
# Expected built mins
BUILDMINS="5"
#Generally cronjob frequency
CHECKTIME="5"
NETWORKNAME="${IMGNAME}_private-network"
#After Image pulling, need to bring up all docker services?
DO_DOCKER_COMPOSE_UP=true
# -------
echo "Eecuting Script @ date and time in YmdHMS: $(date +%Y%m%d%H%M%S)"
set -e
PIDFILE=/Users/Swapnil/Documents/$IMGNAME/forever.pid
if [ -f $PIDFILE ]
then
  PID=$(cat $PIDFILE)
  ps -p $PID > /dev/null 2>&1
  if [ $? -eq 0 ]
  then
    echo "Process already running"
    exit 1
  else
    ## Process not found assume not running
    echo $$
    echo $$ > $PIDFILE
    if [ $? -ne 0 ]
    then
      echo "Could not create PID file"
      exit 1
    fi
  fi
else
  echo $$ > $PIDFILE
  if [ $? -ne 0 ]
  then
    echo "Could not create PID file"
    exit 1
  fi
fi

# Check Docker is running or not; If not runing then exit
if docker info|grep Containers ; then
    echo "Docker is running"
else
    echo "Docker is not running"
    rm $PIDFILE
    exit 1
fi

# Check Container is running or not; and set variable
CONT_INFO=$(docker ps -f "name=$CONTNAME" --format "{{.Names}}")
if [ "$CONT_INFO" = "$CONTNAME" ]; then
    echo "Container is running"
    IS_CONTAINER_RUNNING=true
else
    echo "Container is not running"
    IS_CONTAINER_RUNNING=false
fi


# get token
echo "Retrieving token ..."
TOKEN=$(curl -s -H "Content-Type: application/json" -X POST -d '{"username": "'${UNAME}'", "password": "'${UPASS}'"}' https://hub.docker.com/v2/users/login/ | jq -r .token)

# get list of repositories
echo "Retrieving repository list ..."
REPO_LIST=$(curl -s -H "Authorization: JWT ${TOKEN}" https://hub.docker.com/v2/repositories/${ORG}/?page_size=100 | jq -r '.results|.[]|.name')

# output images & tags
echo "Images and tags for organization: ${ORG}"
echo
for i in ${REPO_LIST}
do
  echo "${i}:"
  # tags
  IMAGE_TAGS=$(curl -s -H "Authorization: JWT ${TOKEN}" https://hub.docker.com/v2/repositories/${ORG}/${i}/tags/?page_size=100 | jq -r '.results|.[]|.name')
  for j in ${IMAGE_TAGS}
  do
    echo "  - ${j}"
  done
  #echo
done

# Check Perticular image is the latest or not
#imm=$(curl -s -H "Authorization: JWT ${TOKEN}" https://hub.docker.com/v2/repositories/${ORG}/${IMGNAME}/tags/?page_size=100)
echo "-----------------"
echo "Last built date details about Image ${IMGNAME} : ${IMGTAG} for organization: ${ORG}"
IMAGE_UPDATED_DATE=$(curl -s -H "Authorization: JWT ${TOKEN}" https://hub.docker.com/v2/repositories/${ORG}/${IMGNAME}/tags/?page_size=100 | jq -r '.results|.[]|select(.name | contains("'${IMGTAG}'")).last_updated')
echo "On Docker Hub IMAGE_UPDATED_DATE---$IMAGE_UPDATED_DATE"
echo "-----------------"

IMAGE_CREATED_DATE=$(docker image inspect ${ORG}/${IMGNAME}:${IMGTAG} | jq -r '.[]|.Created')
echo "Locally IMAGE_CREATED_DATE---$IMAGE_CREATED_DATE"

updatedDate=$(date -jf '%Y-%m-%dT%H:%M' "${IMAGE_UPDATED_DATE:0:16}" +%Y%m%d%H%M%S) 
createdDate=$(date -jf '%Y-%m-%dT%H:%M' "${IMAGE_CREATED_DATE:0:16}" +%Y%m%d%H%M%S)
currentDate=$(date +%Y%m%d%H%M%S)

start_date=$(date -jf "%Y%m%d%H%M%S" "$currentDate" "+%s")
end_date=$(date -jf "%Y%m%d%H%M%S" "$updatedDate" "+%s")
updiffMins=$(( ($start_date - $end_date) / (60) ))
if [[ "$updiffMins" -lt $(($CHECKTIME+1)) ]]; then
        if [ ! -d "${FILEPATH}" ]; then
            mkdir "${FILEPATH}";
        fi
        cd "${FILEPATH}"
        pwd
        echo "updatedDate---$updatedDate" > "ScriptOutput_${currentDate}.txt"
        echo "createdDate---$createdDate" >> "ScriptOutput_${currentDate}.txt"
        echo "currentDate---$currentDate" >> "ScriptOutput_${currentDate}.txt"
        echo "Found after regular checking time -> Docker hub's latest updated image is new; Diff ${updiffMins} mins" >> "ScriptOutput_${currentDate}.txt"
        echo "Script is checking for latest updates after every ${CHECKTIME} mins" >> "ScriptOutput_${currentDate}.txt"
        echo "Fetching all new"
        echo "---------------------------"
        if $IS_CONTAINER_RUNNING ; then
            echo "Container is running"         
        else
            docker-compose down
            echo "Container stopped and removed; Network removed" >> "ScriptOutput_${currentDate}.txt"
        fi
        echo "Image_Created_Date=$currentDate" > ".env"
        echo "ORG=$ORG" >> ".env"
        echo "IMGNAME=$IMGNAME" >> ".env"
        echo "IMGTAG=$IMGTAG" >> ".env"
        echo "CONTNAME=$CONTNAME" >> ".env"
        echo "NETWORKNAME=$NETWORKNAME" >> ".env"
        docker-compose build --no-cache
        echo "Docker Compose built" >> "ScriptOutput_${currentDate}.txt"
        if $DO_DOCKER_COMPOSE_UP ; then
            docker-compose up -d
            echo "Docker services are up now, checked in" >> "ScriptOutput_${currentDate}.txt"  
        else
            echo "Docker services are down, checked in" >> "ScriptOutput_${currentDate}.txt"
        fi
elif [[ "$updatedDate" -gt "$createdDate" ]]; then 
    echo "Updated is latest"
    start_date=$(date -jf "%Y%m%d%H%M%S" "$updatedDate" "+%s")
    end_date=$(date -jf "%Y%m%d%H%M%S" "$createdDate" "+%s")
    diffMins=$(( ($start_date - $end_date) / (60) ))
    if [[ "$BUILDMINS" -lt "$diffMins" ]]; then
        if [ ! -d "${FILEPATH}" ]; then
            mkdir "${FILEPATH}";
        fi
        cd "${FILEPATH}"
        pwd
        echo "updatedDate---$updatedDate" > "ScriptOutput_${currentDate}.txt"
        echo "createdDate---$createdDate" >> "ScriptOutput_${currentDate}.txt"
        echo "currentDate---$currentDate" >> "ScriptOutput_${currentDate}.txt"
        echo "Found after comparing times -> Docker hub's latest updated image is new; Diff ${diffMins} mins" >> "ScriptOutput_${currentDate}.txt"
        echo "Actual image built time is less i.e. ${diffMins} mins than MAX expexted BUILD TIME i.e. ${BUILDMINS} mins" >> "ScriptOutput_${currentDate}.txt"
        echo "Fetching all new" >> "ScriptOutput_${currentDate}.txt"
        echo "-----------------------------"
        if $IS_CONTAINER_RUNNING ; then
            echo "Container is running"         
        else
            docker-compose down
            echo "Container stopped and removed; Network removed" >> "ScriptOutput_${currentDate}.txt"
        fi
        echo "Image_Created_Date=$currentDate" > ".env"
        echo "ORG=$ORG" >> ".env"
        echo "IMGNAME=$IMGNAME" >> ".env"
        echo "IMGTAG=$IMGTAG" >> ".env"
        echo "CONTNAME=$CONTNAME" >> ".env"
        echo "NETWORKNAME=$NETWORKNAME" >> ".env"
        docker-compose build --no-cache
        echo "Docker Compose built" >> "ScriptOutput_${currentDate}.txt"
        if $DO_DOCKER_COMPOSE_UP ; then
            docker-compose up -d
            echo "Docker services are up now" >> "ScriptOutput_${currentDate}.txt"  
        else
            echo "Docker services are down" >> "ScriptOutput_${currentDate}.txt"
        fi
    elif [[ "$BUILDMINS" -gt "$diffMins" ]]; then
        echo "Docker hub's latest updated image is NOT new; Diff ${diffMins} mins"
        echo "Docker images not fetched"
    else
        echo "Docker hub's latest updated image is NOT new; Diff ${diffMins} mins"
        echo "Docker images not fetched"
    fi
elif [[ "$createdDate" -gt "$updatedDate" ]]; then 
    echo "Created is latest"
    start_date=$(date -jf "%Y%m%d%H%M%S" "$createdDate" "+%s")
    end_date=$(date -jf "%Y%m%d%H%M%S" "$updatedDate" "+%s")
    echo "Docker hub has older docker image than local; Older than $(( ($start_date - $end_date) / (60) ))mins"
fi
echo 
echo "------------end---------------"
rm $PIDFILE

这是我的docker-compose文件

version:  "3.2"
services:
  lamp-alpine:
    build:
      context: .
    container_name: "${CONTNAME}"
    image: "${ORG}/${IMGNAME}:${IMGTAG}"
    ports:
      - "127.0.0.1:80:80"
    networks:
      - private-network 

networks:
  private-network:
    driver: bridge

我不打算讨论您是否希望在生产中进行无人值守的更新(我认为不需要)。我只是把这个留在这里作为参考，以防有人觉得有用。在终端中使用以下命令将所有docker映像更新到最新版本:

# docker images | awk '(NR>1) && ($2!~/none/) {print $1":"$2}' | xargs -L1 docker pull

我也遇到过同样的问题，我认为可以通过cron作业每天调用无人值机升级来简单解决。

我的意图是将其作为一种自动和快速的解决方案，以确保生产容器是安全和更新的，因为更新映像和部署具有最新安全更新的新docker映像需要花费一些时间。

也可以使用Github钩子自动化映像的构建和部署

我已经创建了一个基本的docker映像，每天自动检查和安装安全更新(可以通过docker run itech/docker- unattentedupgrade直接运行)。

我还发现了另一种检查容器是否需要更新的方法。

我的完整实现:

Dockerfile

FROM ubuntu:14.04   

RUN apt-get update \
&& apt-get install -y supervisor unattended-upgrades \
&& rm -rf /var/lib/apt/lists/*

COPY install /install
RUN chmod 755 install
RUN /install

COPY start /start
RUN chmod 755 /start

辅助脚本

安装

#!/bin/bash
set -e

cat > /etc/supervisor/conf.d/cron.conf <<EOF
[program:cron]
priority=20
directory=/tmp
command=/usr/sbin/cron -f
user=root
autostart=true
autorestart=true
stdout_logfile=/var/log/supervisor/%(program_name)s.log
stderr_logfile=/var/log/supervisor/%(program_name)s.log
EOF

rm -rf /var/lib/apt/lists/*

ENTRYPOINT ["/start"]

开始

#!/bin/bash

set -e

echo "Adding crontab for unattended-upgrade ..."
echo "0 0 * * * root /usr/bin/unattended-upgrade" >> /etc/crontab

# can also use @daily syntax or use /etc/cron.daily

echo "Starting supervisord ..."
exec /usr/bin/supervisord -n -c /etc/supervisor/supervisord.conf

Edit

我开发了一个小工具docker-run，它作为docker容器运行，可以用来更新所有或选定的运行容器中的包，它也可以用来运行任何任意命令。

可以使用以下命令轻松测试:

Docker run——rm -v /var/run/ Docker .sock:/tmp/ Docker .sockSock itech/docker-run exec

默认情况下，它将在所有运行的容器中执行date命令并显示结果。如果你传递update而不是exec，它将在所有运行的容器中执行apt-get update和apt-get upgrade -y

这里有很多答案，但没有一个符合我的需要。我想知道提问者第一个问题的确切答案。如何知道hub.docker.com上的图像何时更新?

下面的脚本可以每天运行。在第一次运行时，它从HUB注册中心获得标记的基线和更新日期，并将它们保存在本地。从那时起，每次运行它都会检查注册表中的新标记和更新日期。因为每当有新图像存在时，它都会改变，所以它会告诉我们基本图像是否发生了变化。以下是剧本:

#!/bin/bash

DATAPATH='/data/docker/updater/data'

if [ ! -d "${DATAPATH}" ]; then
        mkdir "${DATAPATH}";
fi
IMAGES=$(docker ps --format "{{.Image}}")
for IMAGE in $IMAGES; do
        ORIGIMAGE=${IMAGE}
        if [[ "$IMAGE" != *\/* ]]; then
                IMAGE=library/${IMAGE}
        fi
        IMAGE=${IMAGE%%:*}
        echo "Checking ${IMAGE}"
        PARSED=${IMAGE//\//.}
        if [ ! -f "${DATAPATH}/${PARSED}" ]; then
                # File doesn't exist yet, make baseline
                echo "Setting baseline for ${IMAGE}"
                curl -s "https://registry.hub.docker.com/v2/repositories/${IMAGE}/tags/" > "${DATAPATH}/${PARSED}"
        else
                # File does exist, do a compare
                NEW=$(curl -s "https://registry.hub.docker.com/v2/repositories/${IMAGE}/tags/")
                OLD=$(cat "${DATAPATH}/${PARSED}")
                if [[ "${VAR1}" == "${VAR2}" ]]; then
                        echo "Image ${IMAGE} is up to date";
                else
                        echo ${NEW} > "${DATAPATH}/${PARSED}"
                        echo "Image ${IMAGE} needs to be updated";
                        H=`hostname`
                        ssh -i /data/keys/<KEYFILE> <USER>@<REMOTEHOST>.com "{ echo \"MAIL FROM: root@${H}\"; echo \"RCPT TO: <USER>@<EMAILHOST>.com\"; echo \"DATA\"; echo \"Subject: ${H} - ${IMAGE} needs update\"; echo \"\"; echo -e \"\n${IMAGE} needs update.\n\ndocker pull ${ORIGIMAGE}\"; echo \"\"; echo \".\"; echo \"quit\"; sleep 1; } | telnet <SMTPHOST> 25"
                fi

        fi
done;

您可能需要更改顶部的DATAPATH变量，并更改末尾的电子邮件通知命令以满足您的需要。对我来说，我把它SSH到我的SMTP所在的另一个网络上的服务器上。但是您也可以轻松地使用邮件命令。

现在，您还需要检查容器本身中是否有更新的包。这实际上可能比在容器工作后“拉”更有效。以下是实现这一目标的脚本:

#!/bin/bash


function needsUpdates() {
        RESULT=$(docker exec ${1} bash -c ' \
                if [[ -f /etc/apt/sources.list ]]; then \
                grep security /etc/apt/sources.list > /tmp/security.list; \
                apt-get update > /dev/null; \
                apt-get upgrade -oDir::Etc::Sourcelist=/tmp/security.list -s; \
                fi; \
                ')
        RESULT=$(echo $RESULT)
        GOODRESULT="Reading package lists... Building dependency tree... Reading state information... Calculating upgrade... 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded."
        if [[ "${RESULT}" != "" ]] && [[ "${RESULT}" != "${GOODRESULT}" ]]; then
                return 0
        else
                return 1
        fi
}

function sendEmail() {
        echo "Container ${1} needs security updates";
        H=`hostname`
        ssh -i /data/keys/<KEYFILE> <USRER>@<REMOTEHOST>.com "{ echo \"MAIL FROM: root@${H}\"; echo \"RCPT TO: <USER>@<EMAILHOST>.com\"; echo \"DATA\"; echo \"Subject: ${H} - ${1} container needs security update\"; echo \"\"; echo -e \"\n${1} container needs update.\n\n\"; echo -e \"docker exec ${1} bash -c 'grep security /etc/apt/sources.list > /tmp/security.list; apt-get update > /dev/null; apt-get upgrade -oDir::Etc::Sourcelist=/tmp/security.list -s'\n\n\"; echo \"Remove the -s to run the update\"; echo \"\"; echo \".\"; echo \"quit\"; sleep 1; } | telnet <SMTPHOST> 25"
}

CONTAINERS=$(docker ps --format "{{.Names}}")
for CONTAINER in $CONTAINERS; do
        echo "Checking ${CONTAINER}"
        if needsUpdates $CONTAINER; then
                sendEmail $CONTAINER
        fi
done