1、使用docker commit创建镜像
1）查看容器ID(CONTAINER ID)
docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
d038360bc3b8 cjavapy/oracle11g:latest "/bin/sh -c '/home/o…" 12 hours ago Up 12 hours 0.0.0.0:1521->1521/tcp, :::1521->1521/tcp cjavapy11
83623cd8f70d portainer/portainer-ce "/portainer" 5 weeks ago Up 5 weeks 0.0.0.0:8000->8000/tcp, :::8000->8000/tcp, 0.0.0.0:9000->9000/tcp, :::9000->9000/tcp, 9443/tcp portainer2）通过容器ID(CONTAINER ID)创建镜像
docker commit -m "oracle 11g" d038360bc3b8 cjavapy/oracle11g:latest2、使用docker export和docker import创建镜像
1）查看容器ID(CONTAINER ID)
docker ps -a
2）导出容器到文件
docker export <CONTAINER ID> > img.tar3）加载保存的容器创建镜像
docker import img.tar <IMAGE NAME>:[TAG]
注意：使用此方法也可以将容器进行压缩，另外这样创建的容器可能不能正常启动，我们还需要指定一下启动需要参数，例如，entrypoint、cmd和环境变量等。
3、使用tar导出容器创建镜像
1）进入容器
sudo docker exec -it <CONTAINER ID> /bin/bash2）生成镜像文件
tar -cvf img.tar --exclude=/proc --exclude=/sys --exclude=img.tar /
3）将容器中生成的文件拷贝到宿主机
sudo docker cp <CONTAINER ID>:/img.tar .
4）创建生成镜像
cat img.tar | sudo docker import - <IMAGE NAME>:[TAG]
注意：使用此方法也可以将容器进行压缩，另外这样创建的容器可能不能正常启动，我们还需要指定一下启动需要参数，例如，entrypoint、cmd和环境变量等。
4、查看镜像的Dockerfile的方法
1）使用docker history
通过docker history查看镜像信息来分析生成Dockerfile。但少了FROM指令信息，多出来自BASIC_IMAGE的一些指令信息。
#!/bin/bash
set -u
USAGE_TIPS="Usage: ./dfimage.sh <IMAGE>"
if [ !$1 ];
echo ${USAGE_TIPS}
exit 1
fi
case "$OSTYPE" in
linux*)
docker history --no-trunc --format "{{.CreatedBy}}" $1 | # extract information from layers
tac | # reverse the file
sed 's,^\(|3.*\)\?/bin/\(ba\)\?sh -c,RUN,' | # change /bin/(ba)?sh calls to RUN
sed 's,^RUN #(nop) *,,' | # remove RUN #(nop) calls for ENV,LABEL...
sed 's, *&& *, \\\n \&\& ,g' # pretty print multi command lines following Docker best practices
;;
darwin*)
docker history --no-trunc --format "{{.CreatedBy}}" $1 | # extract information from layers
tail -r | # reverse the file
sed -E 's,^(\|3.*)?/bin/(ba)?sh -c,RUN,' | # change /bin/(ba)?sh calls to RUN
sed 's,^RUN #(nop) *,,' | # remove RUN #(nop) calls for ENV,LABEL...
sed $'s, *&& *, \\\ \\\n \&\& ,g' # pretty print multi command lines following Docker best practices
;;
*)
echo "unknown OSTYPE: $OSTYPE"
;;
esac将上面内容存为dfimage.sh，使用方法如下，
dfimage hanxiao/mynginx:4.1
2）使用DockerImage2Df容器工具
# 命令alias
echo "alias image2df='docker run -v /var/run/docker.sock:/var/run/docker.sock --rm cucker/image2df'" >> ~/.bashrc
. ~/.bashrc
# 使用方法
image2df <IMAGE项目地址：https://github.com/cucker0/dockerimage2df
$ echo "alias image2df='docker run -v /var/run/docker.sock:/var/run/docker.sock --rm cucker/image2df'" >> ~/.bashrc
$ . ~/.bashrc
$ docker pull mysql
$ image2df mysql
========== Dockerfile ==========
FROM mysql:latest
RUN groupadd -r mysql && useradd -r -g mysql mysql
RUN apt-get update && apt-get install -y --no-install-recommends gnupg dirmngr && rm -rf /var/lib/apt/lists/*
ENV GOSU_VERSION=1.12
RUN set -eux; \
savedAptMark="$(apt-mark showmanual)"; \
apt-get update; \
apt-get install -y --no-install-recommends ca-certificates wget; \
rm -rf /var/lib/apt/lists/*; \
dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')"; \
wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \
wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \
export GNUPGHOME="$(mktemp -d)"; \
gpg --batch --keyserver hkps://keys.openpgp.org --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
gpgconf --kill all; \
rm -rf "$GNUPGHOME" /usr/local/bin/gosu.asc; \
apt-mark auto '.*' > /dev/null; \
[ -z "$savedAptMark" ] || apt-mark manual $savedAptMark > /dev/null; \
apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \
chmod +x /usr/local/bin/gosu; \
gosu --version; \
gosu nobody true
RUN mkdir /docker-entrypoint-initdb.d
RUN apt-get update && apt-get install -y --no-install-recommends \
pwgen \
openssl \
perl \
xz-utils \
&& rm -rf /var/lib/apt/lists/*
RUN set -ex; \
key='A4A9406876FCBD3C456770C88C718D3B5072E1F5'; \
export GNUPGHOME="$(mktemp -d)"; \
gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$key"; \
gpg --batch --export "$key" > /etc/apt/trusted.gpg.d/mysql.gpg; \
gpgconf --kill all; \
rm -rf "$GNUPGHOME"; \
apt-key list > /dev/null
ENV MYSQL_MAJOR=8.0
ENV MYSQL_VERSION=8.0.24-1debian10
RUN echo 'deb http://repo.mysql.com/apt/debian/ buster mysql-8.0' > /etc/apt/sources.list.d/mysql.list
RUN { \
echo mysql-community-server mysql-community-server/data-dir select ''; \
echo mysql-community-server mysql-community-server/root-pass password ''; \
echo mysql-community-server mysql-community-server/re-root-pass password ''; \
echo mysql-community-server mysql-community-server/remove-test-db select false; \
} | debconf-set-selections \
&& apt-get update \
&& apt-get install -y \
mysql-community-client="${MYSQL_VERSION}" \
mysql-community-server-core="${MYSQL_VERSION}" \
&& rm -rf /var/lib/apt/lists/* \
&& rm -rf /var/lib/mysql && mkdir -p /var/lib/mysql /var/run/mysqld \
&& chown -R mysql:mysql /var/lib/mysql /var/run/mysqld \
&& chmod 1777 /var/run/mysqld /var/lib/mysql
VOLUME [/var/lib/mysql]
COPY dir:2e040acc386ebd23b8571951a51e6cb93647df091bc26159b8c757ef82b3fcda in /etc/mysql/
COPY file:345a22fe55d3e6783a17075612415413487e7dba27fbf1000a67c7870364b739 in /usr/local/bin/
RUN ln -s usr/local/bin/docker-entrypoint.sh /entrypoint.sh # backwards compat
ENTRYPOINT ["docker-entrypoint.sh"]
EXPOSE 3306 33060
CMD ["mysqld"]