假设我们有一个场景，所有服务器共享同一份配置文件，我们肯定不可能单独手动维护每台服务器，这时可以利用zookeeper的配置管理功能。
环境：python + nginx + zookeeper
目的：当zookeeper中的配置文件发生变化时nginx自动拉取最新配置文件并应用到本地，最终重启服务器：
一。搭建zookeeper集群：
步骤略，请参考：http://zookeeper.apache.org/doc/r3.4.13/zookeeperStarted.html
请确保zookeeper集群为健康状态：
二。安装nginx
yum install nginx -y
启动nginx： systemctl start nginx
三。编写python zookeeper 客户端：
目的：定期连接zookeeper集群，检测配置文件发生变化：
from kazoo.client import KazooClient
import time
zk=KazooClient(hosts='192.168.85.137:2181')
zk.start() Version=None
while True:
@zk.DataWatch("/nginx")
def watch_node(data, stat):
global Version
if Version == None:
Version=stat
if Version != stat:
Version = stat
nginx_file=str(data,encoding='utf-8')
print("配置已改变！！！！！")
f=open('nginx.conf','w',encoding='utf-8')
f.write(nginx_file)
f.flush()
f.close()
import os
Path=os.path.dirname(os.path.abspath(__file__))
os.system('cp -f %s/nginx.conf /etc/nginx/nginx.conf && systemctl restart nginx.service'%Path) #替换nginx配置文件，然后重启服务，注意，这这里只是写了一个大体框架，生产环境一定不要直接重启，可以写一些判断，至少应该先确保配置文件没有错误再重启nginx
time.sleep()
测试：修改zookeeper中的nginx配置，看客户端是否能拉去配置文件：
from kazoo.client import KazooClient
import time
zk=KazooClient(hosts='192.168.85.137:2181')
zk.start() nginx_config="""
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
include /usr/share/nginx/modules/*.conf;
events {
worker_connections 1024;
}
http {
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 /var/log/nginx/access.log main;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;
include /etc/nginx/mime.types;
default_type application/octet-stream;
include /etc/nginx/conf.d/*.conf;
server {
listen 5555 default_server;
index index.php index.html;
server_name _;
root /usr/share/nginx/html;
include /etc/nginx/default.d/*.conf; location ~ \.php$ {
fastcgi_pass 127.0.0.1:9000;
fastcgi_index index.php;
#fastcgi_param SCRIPT_FILENAME /scripts$fastcgi_script_name;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_param PATH_INFO $fastcgi_path_info;
include fastcgi_params;
} error_page 404 /404.html;
location = /40x.html {
} error_page 500 502 503 504 /50x.html;
location = /50x.html {
}
}
} """
zk.set('/nginx',bytes(nginx_config,encoding='utf-8'))
成功！！！