【Docker专题】Docker-Compose 容器集群的快速编排方法
Docker-Compose 容器集群的快速编排
Docker-compose 简介
- Docker-Compose项目是Docker官方的开源项目，负责实现对Docker容器集群的快速编排。
- Docker-Compose将所管理的容器分为三层，分别是 工程（project），服务（service）以及容器（container）。Docker-Compose运行目录下的所有文件（docker-compose.yml，extends文件或环境变量文件等）组成一个工程，若无特殊指定工程名即为当前目录名。一个工程当中可包含多个服务，每个服务中定义了容器运行的镜像、参数、依赖。一个服务当中可包括多个容器实例，Docker-Compose并没有解决负载均衡的问题，因此需要借助其它工具实现服务发现及负载均衡，比如 Consul。
- Docker-Compose的工程配置文件默认为docker-compose.yml，可通过环境变量COMPOSE_FILE或-f参数自定义配置文件，其定义了多个有依赖关系的服务及每个服务运行的容器。
- 使用一个Dockerfile模板文件，可以让用户很方便的定义一个单独的应用容器。在工作中，经常会碰到需要多个容器相互配合来完成某项任务的情况。例如要实现一个Web项目，除了Web服务容器本身，往往还需要再加上后端的数据库服务容器，甚至还包括负载均衡容器等。
- Compose允许用户通过一个单独的docker-compose.yml模板文件（YAML 格式）来定义一组相关联的应用容器为一个项目（project）。
- Docker-Compose项目由Python编写，调用Docker服务提供的API来对容器进行管理。因此，只要所操作的平台支持Docker API， 就可以在其上利用Compose来进行编排管理。
compose 部署
Docker Compose 环境安装
Docker Compose 是 Docker 的独立产品，因此需要安装 Docker 之后在单独安装 Docker Compose
curl -L https://github.com/docker/compose/releases/download/1.21.1/docker-compose-`uname -s`-`uname -m` -o /usr/local/bin/docker-compose
#或者已下载过直接从宿主机传入到/opt目录下
mv docker-compose /usr/local/bin/
#安装
chmod +x /usr/local/bin/docker-compose
#查看版本
docker-compose –version
YAML 文件格式及编写注意事项
- YAML 是一种标记语言，它可以很直观的展示数据序列化格式，可读性高。类似于 XML数据描述语言，语法比 XML 简单的很多。YAML 数据结构通过缩进来表示，连续的项目通过减号来表示，键值对用冒号分隔，数组用中括号 [ ] 括起来， hash 用花括号 { } 括起来。
- YAML 文件格式及编写注意事项
- 大小与敏感
- 通过缩进表示层级关系
- 不支持制表符tab键缩进，只能使用空格缩进
- 缩进的空格数目不重要，只要相同层级左对齐，通常开头缩进2个空格
- 用#号注释
- 符号字符后缩进1个空格，如冒号：、逗号，、横杠-
Docker Compose配置常用字段
| 字段 | 描述 |
|---|---|
| build | 指定Dockerfile文件名（要指定的Dockerfile文件需要在build标签的子级标签中用dockerfile标签指定） |
| dockerfile | 构建镜像上下文路径 |
| context | 可以是dockerfile路径，或者是执行git 仓库的url地址 |
| image | 指定镜像（已存在） |
| command | 执行命令，会覆盖容器启动后默认执行的命令（会覆盖Dockerfile的CMD指令） |
| container_name | 指定容器名称，由于容器名称是唯一的，如果指定自定义名称，则无法scale |
| deploy | 指定部署和运行服务相关配置，只能在Swarm模式使用 |
| enviroment | 添加环境变量 |
| networks | 加入网络，引用顶级networks下条目 |
| networks-mode | 设置容器的网络模式，host、bridge….. |
| ports | 暴露容器端口，与-p 相同，但是端口不能低于60 |
| volumes | 挂载一个宿主机目录或命令卷到容器，命名卷要在顶级volumes 定义卷名称 |
| volumes_from | 从另一个服务或容器挂载卷，可选参数 :ro 和 :rw，仅版本'2'支持 |
| hostname | 容器主机名 |
| sysctls | 在容器内设置内核参数 |
| links | 连接到另一个容器，- 服务名称[ :服务别名 ] |
| privilcgcd | 用来给容器root权限，注意是不安全的，truc|false（开启|关闭） |
| restart | 重启策略，定义是否重启容器； no（默认，不重启）， always（总是重启）， on-failure,（退出状态非0时重启）, on-failure:3 ,在容器非正常退出时重启容器，最多重启3次， unless-stoped 在容器退出时总是重启容器，但是不考虑在Docker 守护进程启动时就已经停止了的容器 |
| depends_on | 此标签用于解决容器的依赖，启动先后问题。如启动应用容器，需要先启动数据库容器php: depends_on: – apache – mysql |
Docker compose 常用命令字段
| 字段 | 描述 |
|---|---|
| build | 重新构建服务 |
| ps | 列出容器 |
| up | 创建和启动容器 |
| exec | 在容器里面执行命令 |
| scale | 指定一个服务容器启动数量 |
| top | 显示正在运行的容器进程 |
| logs | 查看服务容器的输出 |
| down | 删除容器、网络、数据卷和镜像 |
| stop/start/restart | 停止/启动/重启服务 |
编写Docker Compose搭建lnmp论坛
部署前准备
net.ipv4.ip_forward = 1 #末行添加
sysctl -p #刷新配置
systemctl restart docker #重启docker服务
配置nginx
编写dockerfile文件
MAINTAINER this is nginx images<gb>
RUN yum -y install pcre-devel zlib-devel gcc gcc-c++ make
RUN useradd -M -s /sbin/nologin nginx
ADD nginx-1.12.0.tar.gz /opt/
WORKDIR /opt/nginx-1.12.0/
RUN ./configure \
–prefix=/usr/local/nginx \
–user=nginx \
–group=nginx \
–with-http_stub_status_module && make -j4 && make install
ENV PATH $PATH:/usr/local/nginx/sbin
ADD nginx.conf /usr/local/nginx/conf/
RUN chmod 777 -R /usr/local/nginx/html/
EXPOSE 80
EXPOSE 443
CMD [“/usr/local/nginx/sbin/nginx”, “-g”, “daemon off;”]
准备配置好nginx配置文件（添加支持php解析配置）
worker_processes 1;
#error_log logs/error.log;
#error_log logs/error.log notice;
#error_log logs/error.log info;
#pid logs/nginx.pid;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
#log_format main ‘$remote_addr – $remote_user [$time_local] “$request” ‘
# ‘$status $body_bytes_sent “$http_referer” ‘
# ‘”$http_user_agent” “$http_x_forwarded_for”‘;
#access_log logs/access.log main;
sendfile on;
#tcp_nopush on;
#keepalive_timeout 0;
keepalive_timeout 65;
#gzip on;
server {
listen 80;
server_name localhost;
charset utf-8;
#access_log logs/host.access.log main;
location / {
root html;
index index.html index.php;
}
#error_page 404 /404.html;
# redirect server error pages to the static page /50x.html
#
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
# proxy the PHP scripts to Apache listening on 127.0.0.1:80
#
#location ~ \.php$ {
# proxy_pass http://127.0.0.1;
#}
# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
#
location ~ \.php$ {
root html;
fastcgi_pass 172.18.0.30:9000;
fastcgi_index index.php;
fastcgi_param SCRIPT_FILENAME /usr/local/nginx/html$fastcgi_script_name;
include fastcgi_params;
}
# deny access to .htaccess files, if Apache’s document root
# concurs with nginx’s one
#
#location ~ /\.ht {
# deny all;
#}
}
# another virtual host using mix of IP-, name-, and port-based configuration
#
#server {
# listen 8000;
# listen somename:8080;
# server_name somename alias another.alias;
# location / {
# root html;
# index index.html index.htm;
# }
#}
# HTTPS server
#
#server {
# listen 443 ssl;
# server_name localhost;
# ssl_certificate cert.pem;
# ssl_certificate_key cert.key;
# ssl_session_cache shared:SSL:1m;
# ssl_session_timeout 5m;
# ssl_ciphers HIGH:!aNULL:!MD5;
# ssl_prefer_server_ciphers on;
# location / {
# root html;
# index index.html index.htm;
# }
#}
}
折叠
配置mysql
准备配置文件
[client]
port = 3306
socket=/usr/local/mysql/mysql.sock
[mysqld]
user = mysql
basedir=/usr/local/mysql
datadir=/usr/local/mysql/data
port = 3306
character-set-server=utf8
pid-file = /usr/local/mysql/mysqld.pid
socket=/usr/local/mysql/mysql.sock
bind-address = 0.0.0.0
skip-name-resolve
max_connections=2048
default-storage-engine=INNODB
max_allowed_packet=16M
server-id = 1
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_AUTO_VALUE_ON_ZERO,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,PIPES_AS_CONCAT,ANSI_QUOTES
编写dockerfile文件
MAINTAINER this is mysql image <lnmp>
RUN yum -y install gcc gcc-c++ ncurses ncurses-devel bison cmake make;useradd -M -s /sbin/nologin mysql
ADD mysql-boost-5.7.20.tar.gz /usr/local/src/
WORKDIR /usr/local/src/mysql-5.7.20/
RUN cmake \
-DCMAKE_INSTALL_PREFIX=/usr/local/mysql \
-DMYSQL_UNIX_ADDR=/usr/local/mysql/mysql.sock \
-DSYSCONFDIR=/etc \
-DSYSTEMD_PID_DIR=/usr/local/mysql \
-DDEFAULT_CHARSET=utf8 \
-DDEFAULT_COLLATION=utf8_general_ci \
-DWITH_EXTRA_CHARSETS=all \
-DWITH_INNOBASE_STORAGE_ENGINE=1 \
-DWITH_ARCHIVE_STORAGE_ENGINE=1 \
-DWITH_BLACKHOLE_STORAGE_ENGINE=1 \
-DWITH_PERFSCHEMA_STORAGE_ENGINE=1 \
-DMYSQL_DATADIR=/usr/local/mysql/data \
-DWITH_BOOST=boost \
-DWITH_SYSTEMD=1;make -j 4;make install
ADD my.cnf /etc/my.cnf
EXPOSE 3306
RUN chown -R mysql:mysql /usr/local/mysql/;chown mysql:mysql /etc/my.cnf
WORKDIR /usr/local/mysql/bin/
RUN ./mysqld \
–initialize-insecure \
–user=mysql \
–basedir=/usr/local/mysql \
–datadir=/usr/local/mysql/data;cp /usr/local/mysql/usr/lib/systemd/system/mysqld.service /usr/lib/systemd/system/;systemctl enable mysqld
ENV PATH=/usr/local/mysql/bin:/usr/local/mysql/lib:$PATH
VOLUME [ “/usr/local/mysql” ]
CMD [“/usr/sbin/init”]
配置php
编写Dockerfile文件
MAINTAINER this is php image <lnmp>
RUN yum install -y gd \
libjpeg libjpeg-devel \
libpng libpng-devel \
freetype freetype-devel \
libxml2 libxml2-devel \
zlib zlib-devel \
curl curl-devel \
openssl openssl-devel \
gcc gcc-c++ make pcre-devel;useradd -M -s /sbin/nologin nginx
ADD php-7.1.10.tar.bz2 /usr/local/src/
WORKDIR /usr/local/src/php-7.1.10
RUN ./configure \
–prefix=/usr/local/php \
–with-mysql-sock=/usr/local/mysql/mysql.sock \
–with-mysqli \
–with-zlib \
–with-curl \
–with-gd \
–with-jpeg-dir \
–with-png-dir \
–with-freetype-dir \
–with-openssl \
–enable-fpm \
–enable-mbstring \
–enable-xml \
–enable-session \
–enable-ftp \
–enable-pdo \
–enable-tokenizer \
–enable-zip ; make -j 4 ; make install
ENV PATH /usr/local/php/bin:/usr/local/php/sbin:$PATH
ADD php.ini /usr/local/php/lib/
ADD php-fpm.conf /usr/local/php/etc/
RUN rm -rf /usr/local/php/etc/php-fpm.d/www.conf.default
ADD www.conf /usr/local/php/etc/php-fpm.d/
EXPOSE 9000
CMD /usr/local/php/sbin/php-fpm -F
将所需的三个配置文件修改后写入
[global]
pid = run/php-fpm.pid
include=/usr/local/php/etc/php-fpm.d/*.conf
vim php.ini
[PHP]
engine = On
short_open_tag = Off
precision = 14
output_buffering = 4096
zlib.output_compression = Off
implicit_flush = Off
unserialize_callback_func =
serialize_precision = -1
disable_functions =
disable_classes =
zend.enable_gc = On
expose_php = On
max_execution_time = 30
max_input_time = 60
memory_limit = 128M
error_reporting = E_ALL
display_errors = On
display_startup_errors = On
log_errors = On
log_errors_max_len = 1024
ignore_repeated_errors = Off
ignore_repeated_source = Off
report_memleaks = On
track_errors = On
html_errors = On
variables_order = “GPCS”
request_order = “GP”
register_argc_argv = Off
auto_globals_jit = On
post_max_size = 8M
auto_prepend_file =
auto_append_file =
default_mimetype = “text/html”
default_charset = “UTF-8”
doc_root =
user_dir =
enable_dl = Off
file_uploads = On
upload_max_filesize = 2M
max_file_uploads = 20
allow_url_fopen = On
allow_url_include = Off
default_socket_timeout = 60
[CLI Server]
cli_server.color = On
[Date]
date.timezone = Asia/Shanghai
[filter]
[iconv]
[intl]
[sqlite3]
[Pcre]
[Pdo]
[Pdo_mysql]
pdo_mysql.cache_size = 2000
pdo_mysql.default_socket=
[Phar]
[mail function]
SMTP = localhost
smtp_port = 25
mail.add_x_header = On
[SQL]
sql.safe_mode = Off
[ODBC]
odbc.allow_persistent = On
odbc.check_persistent = On
odbc.max_persistent = -1
odbc.max_links = -1
odbc.defaultlrl = 4096
odbc.defaultbinmode = 1
[Interbase]
ibase.allow_persistent = 1
ibase.max_persistent = -1
ibase.max_links = -1
ibase.timestampformat = “%Y-%m-%d %H:%M:%S”
ibase.dateformat = “%Y-%m-%d”
ibase.timeformat = “%H:%M:%S”
[MySQLi]
mysqli.max_persistent = -1
mysqli.allow_persistent = On
mysqli.max_links = -1
mysqli.cache_size = 2000
mysqli.default_port = 3306
mysqli.default_socket = /usr/local/mysql/mysql.sock
mysqli.default_host =
mysqli.default_user =
mysqli.default_pw =
mysqli.reconnect = Off
[mysqlnd]
mysqlnd.collect_statistics = On
mysqlnd.collect_memory_statistics = On
[OCI8]
[PostgreSQL]
pgsql.allow_persistent = On
pgsql.auto_reset_persistent = Off
pgsql.max_persistent = -1
pgsql.max_links = -1
pgsql.ignore_notice = 0
pgsql.log_notice = 0
[bcmath]
bcmath.scale = 0
[browscap]
[Session]
session.save_handler = files
session.use_strict_mode = 0
session.use_cookies = 1
session.use_only_cookies = 1
session.name = PHPSESSID
session.auto_start = 0
session.cookie_lifetime = 0
session.cookie_path = /
session.cookie_domain =
session.cookie_httponly =
session.serialize_handler = php
session.gc_probability = 1
session.gc_divisor = 1000
session.gc_maxlifetime = 1440
session.referer_check =
session.cache_limiter = nocache
session.cache_expire = 180
session.use_trans_sid = 0
session.sid_length = 26
session.trans_sid_tags = “a=href,area=href,frame=src,form=”
session.sid_bits_per_character = 5
[Assertion]
zend.assertions = 1
[COM]
[mbstring]
[gd]
[exif]
[Tidy]
tidy.clean_output = Off
[soap]
soap.wsdl_cache_enabled=1
soap.wsdl_cache_dir=”/tmp”
soap.wsdl_cache_ttl=86400
soap.wsdl_cache_limit = 5
[sysvshm]
[ldap]
ldap.max_links = -1
[mcrypt]
[dba]
[opcache]
[curl]
[openssl]
vim php-fpm.conf
[global]
pid = run/php-fpm.pid
include=/usr/local/php/etc/php-fpm.d/*.conf
折叠
vim www.conf
[www]
user = nginx
group = nginx
listen = 172.18.0.30:9000
pm = dynamic
pm.max_children = 5
pm.start_servers = 2
pm.min_spare_servers = 1
pm.max_spare_servers = 3
编写docker-compose.yml文件
services:
nginx:
container_name: nginx
build:
context: ./nginx
dockerfile: Dockerfile
ports:
– 80:80
networks:
lnmp:
ipv4_address: 172.18.0.10
mysql:
container_name: mysql
privileged: true
build:
context: ./mysql
dockerfile: Dockerfile
ports:
– 3306:3306
networks:
lnmp:
ipv4_address: 172.18.0.20
php:
depends_on:
– nginx
– mysql
build:
context: ./php
dockerfile: Dockerfile
container_name: php
ports:
– 9000:9000
networks:
lnmp:
ipv4_address: 172.18.0.30
volumes_from:
– nginx
– mysql
networks:
lnmp:
driver: bridge
ipam:
config:
– subnet: 172.18.0.0/16
折叠
#启动容器
docker-compose -f docker-compose.yml up -d
docker ps -a
