Docker容器与容器云之Docker单机集群部署案例
准备工作：
CentOS 7安装docker：
#yum -y install docker
1、获取节点所需镜像
--主机执行
#docker pull django
#docker pull haproxy
#docker pull redis
# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
docker.io/haproxy latest d2deb2e11e09 6 days ago 135.5 MB
docker.io/redis latest 4e482b286430 13 days ago 98.95 MB
docker.io/django latest eb40dcf64078 6 months ago 436 MB
2、启动各个容器
--主机执行
# 启动redis容器
sudo docker run -it --name redis-master redis /bin/bash
sudo docker run -it --name redis-slave1 --link redis-master:master redis /bin/bash
sudo docker run -it --name redis-slave2 --link redis-master:master redis /bin/bash
# 启动django容器
sudo docker run -it --name APP1 --link redis-master:db -v ~/Projects/Django/App1:/usr/src/app django /bin/bash
sudo docker run -it --name APP2 --link redis-master:db -v ~/Projects/Django/App2:/usr/src/app django /bin/bash
# 启动haproxy容器
sudo docker run -it --name HAProxy --link APP1:APP1 --link APP2:APP2 -p 6301:6301 -v ~/Projects/HAProxy:/tmp haproxy /bin/bash
# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
61ceae4c7c85 haproxy "/docker-entrypoint.s" 8 hours ago Up 8 hours 0.0.0.0:6301->6301/tcp HAProxy
7b11baf7b2fd django "/bin/bash" 8 hours ago Up 8 hours app2
bdb9ddacefdb django "/bin/bash" 8 hours ago Up 8 hours app1
2877a5829a6d redis "docker-entrypoint.sh" 8 hours ago Up 8 hours 6379/tcp redis-slave2
a39b414d570c redis "docker-entrypoint.sh" 8 hours ago Up 8 hours 6379/tcp redis-slave1
c7c22a1a4123 redis "docker-entrypoint.sh" 8 hours ago Up 8 hours 6379/tcp redis-master
3、redis节点配置
主机操作，切换到容器挂载目录下，进行master节点配置：
# docker inspect --format "{{ .Config.Volumes }}" c7c22a1a4123
map[/data:{}]
# docker inspect c7c22a1a4123 | grep Source
"Source": "/var/lib/docker/volumes/4e823da40e15260dc5865060ce54d11b34f7527c37f1f55cbd4457f411ac7905/_data",
#cd /var/lib/docker/volumes/4e823da40e15260dc5865060ce54d11b34f7527c37f1f55cbd4457f411ac7905/_data
#cp <your-own-redis-dir>/redis.conf redis.conf
#vim redis.conf
修改以下内容：
bind 0.0.0.0
daemonize yes
pidfile /var/run/redis.pid
容器内操作，启动redis master节点服务：
#cd /data
#cp redis.conf /usr/local/bin
#cd /usr/local/bin
#redis-server redis.conf
4、配置redis slave节点
主机操作配置redis配置文件：
# docker inspect --format "{{ .Config.Volumes }}" a39b414d570c
map[/data:{}]
# docker inspect a39 | grep Source
"Source": "/var/lib/docker/volumes/3c4ae73e1457456daf67ee0c03c33a41f855edc9c1c5d7226ef8119e3804561b/_data",
#cd /var/lib/docker/volumes/3c4ae73e1457456daf67ee0c03c33a41f855edc9c1c5d7226ef8119e3804561b/_data
#cp <your-own-redis-dir>/redis.conf redis.conf
#vim redis.conf
修改以下内容：
bind 0.0.0.0
daemonize yes
pidfile /var/run/redis.pid
slaveof master 6379
切换到redis slave1节点容器下执行：
#cd /data
#cp redis.conf /usr/local/bin
#cd /usr/local/bin
#redis-server redis.conf
同理启动redis另一个从节点。
至此redis配置完成，进行redis功能测试：
以redis-cli方式登录redis master节点：
# redis-cli
127.0.0.1:6379> set master c7c2
OK
127.0.0.1:6379> get master
"c7c2"
127.0.0.1:6379> quit
以redis-cli方式登录redis slave节点：
# redis-cli
127.0.0.1:6379> get master
"c7c2"
127.0.0.1:6379> quit
Slave节点能正常接收主节点设置，说明redis配置成功。
5、app容器节点配置
App容器内安装python语言redis支持包：
#pip install redis
测试：
# python
Python 3.4.5 (default, Dec 14 2016, 18:54:20)
[GCC 4.9.2] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import redis
>>> print(redis.__file__)
/usr/local/lib/python3.4/site-packages/redis/__init__.py
>>> quit()
6、创建app：
容器内：
#cd /usr/src/app
#mkdir dockerapp ##注意，这里需要关闭主机的selinux功能，关闭方式：setenforce 0
#cd dockerapp
# django-admin.py startproject redisweb
# ls
redisweb
# cd redisweb/
# ls
manage.py redisweb
# python manage.py startapp helloworld
# ls
helloworld manage.py redisweb
主机内：
# cd ~/Projects/Django/App1/
# ls
dockerweb
# cd dockerweb/redisweb/helloworld/
# ls
admin.py apps.py __init__.py migrations models.py __pycache__ tests.py views.py
# vim views.py
内容如下：
from django.shortcuts import render
from django.http import HttpResponse
# Create your views here.
import redis
def hello(request):
str=redis.__file__
str+="<br>"
r = redis.Redis(host='db',port=6379,db=0)
info=r.info()
str+=("Set Hi <br>")
r.set('Hi','Helloworld-app1')
str+=("Get Hi:%s <br>" % r.get('Hi'))
str+=("Redis Info: <br>")
str+=("Key : Info Value")
for key in info:
str+=("%s:%s <br>" % (key,info[key]))
return HttpResponse(str)
编辑settings.py文件：
# ls
__init__.py __pycache__ settings.py urls.py wsgi.py
# vim settings.py
修改内容如下：
ALLOWED_HOSTS = ['*'] --此处需要修改
# Application definition
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'helloworld', --添加此处
]
最后再修改urls.py文件：
# vim urls.py
修改后内容如下：
from django.conf.urls import include,url
from django.contrib import admin
from helloworld.views import hello
urlpatterns = [
url(r'^admin/', include(admin.site.urls)),
url(r'^helloworld$',hello),
]
进入app容器，完成项目的生成：
# python manage.py makemigrations
No changes detected
# python manage.py migrate
Operations to perform:
Apply all migrations: admin, auth, contenttypes, sessions
Running migrations:
Applying contenttypes.0001_initial... OK
Applying auth.0001_initial... OK
Applying admin.0001_initial... OK
Applying admin.0002_logentry_remove_auto_add... OK
Applying contenttypes.0002_remove_content_type_name... OK
Applying auth.0002_alter_permission_name_max_length... OK
Applying auth.0003_alter_user_email_max_length... OK
Applying auth.0004_alter_user_username_opts... OK
Applying auth.0005_alter_user_last_login_null... OK
Applying auth.0006_require_contenttypes_0002... OK
Applying auth.0007_alter_validators_add_error_messages... OK
Applying auth.0008_alter_user_username_max_length... OK
Applying sessions.0001_initial... OK
# python manage.py createsuperuser
Username (leave blank to use 'root'):
Email address:
Password:
Password (again):
This password is too short. It must contain at least 8 characters.
Password:
Password (again):
Superuser created successfully.
至此，app节点配置完成，按照相同步骤配置app节点2.
容器内启动两个app节点：
# python manage.py runserver 0.0.0.0:8001
# python manage.py runserver 0.0.0.0:8002
7、haproxy节点配置
主机操作：
# cd ~/Projects/HAProxy/
#vim haproxy.cfg
内容如下：
global
log 127.0.0.1 local0
maxconn 4096
chroot /usr/local/sbin
daemon
nbproc 4
pidfile /usr/local/sbin/haproxy.pid
defaults
log 127.0.0.1 local3
mode http
option dontlognull
option redispatch
retries 2
maxconn 2000
balance roundrobin
timeout connect 5000ms
timeout client 50000ms
timeout server 50000ms
listen redis_proxy
bind 0.0.0.0:6301
stats enable
stats uri /haproxy-stats
server app1 app1:8001 check inter 2000 rise 2 fall 5
server app2 app2:8002 check inter 2000 rise 2 fall 5
进入容器，启动haproxy负载均衡服务：
#cd /usr/local/sbin
# cp /tmp/haproxy.cfg haproxy.cfg
# haproxy -f haproxy.cfg
至此，代理服务配置完成。
应用测试：
客户机登录：http://192.168.100.235:6301/helloworld
客户机也可以登录后台管理界面：http://192.168.100.235:6301/haproxy-stats
