我们可以使用 Docker 镜像快速运行 Sentinel Dashboard

docker run -p 8858:8858 bladex/sentinel-dashboard

再使用默认的用户名/密码：sentinel/seltinel 登录，然后你就可以看到很强大的控制台界面了

基于 Docker 快速启动一个使用 Derby 数据库、单机模式的 Nacos 用于测试

docker run --env MODE=standalone nacos/nacos-server

使用浏览器打开启动提示中的 Console 地址：http://10.0.0.8:8848/nacos/index.html，输入默认用户名/密码：nacos/nacos，即可开始测试体验。

docker volume create portainer_data
docker run -d -p 9000:9000 --name portainer --restart always -v /var/run/docker.sock:/var/run/docker.sock -v portainer_data:/data portainer/portainer 

服务器上使用 PHP SoapClient 作为 WebService 客户端调用第三方接口，发现存在大量 CLOSE-WAIT 状态 TCP 连接。

解决办法是设置 keep_alive 参数，使 SoapClient 不保持连接，具体 PHP 代码如下：

<?php
new SoapClient("http://webservice.test/", [
    "keep_alive" => false,
]);

wget https://github.com/apache/dubbo-admin/archive/0.2.0.tar.gz
tar zxvf 0.2.0.tar.gz
cd dubbo-admin-0.2.0
./mvnw clean package
java -jar dubbo-admin-distribution/target/dubbo-admin-0.2.0.jar --server.port=8081

brew install zookeeper
brew services start zookeeper

sudo apt-get install linuxbrew-wrapper
brew help

yum install -y epel-release
yum install -y nginx

sudo apt install zookeeperd
sudo systemctl enable zookeeper
sudo systemctl restart zookeeper

[email protected]:/var/lib/zookeeper# /usr/share/zookeeper/bin/zkCli.sh
Connecting to localhost:2181
Welcome to ZooKeeper!
JLine support is enabled
WATCHER::
WatchedEvent state:SyncConnected type:None path:null

[zk: localhost:2181(CONNECTED) 0] ls /
[zookeeper]
[zk: localhost:2181(CONNECTED) 1]

[zk: localhost:2181(CONNECTED) 0] create /config.json {}
Created /config.json
[zk: localhost:2181(CONNECTED) 1]

[zk: localhost:2181(CONNECTED) 0] get /config.json
{}
cZxid = 0xb
ctime = Fri Apr 03 17:27:50 GMT+00:00 2020
mZxid = 0xb
mtime = Fri Apr 03 17:27:50 GMT+00:00 2020
pZxid = 0xb
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 2
numChildren = 0
[zk: localhost:2181(CONNECTED) 1]

[zk: localhost:2181(CONNECTED) 0] delete /config.json
[zk: localhost:2181(CONNECTED) 1]

brew install deployer