终端连接服务器

ssh root@XXX.XXX.XXX.XX //公网IP

遇到错误

ssh: connect to host XXX.XX.XX.XX port 22: Operation timed out

排查

PING 一下看看能不能ping得通

telnet XXX.XX.XXX.XX 22

结果丢包了

Trying XXX.XX.XX.XX...
telnet: connect to address XXX.XX.XX.XX: Operation timed out
telnet: Unable to connect to remote host

使用链路测试工具：

参考：链路测试工具使用说明

经过一番折腾，发现是阿里云服务器需要配置安全组规则…沃日太坑爹了。

设置好折后就OK能连上了。

ssh -p 22 root@XXX.XX.XX.XX
The authenticity of host 'XXX.XX.XX.XX (XXX.XX.XX.XX)' can't be established.
ECDSA key fingerprint is SHA256:oZmWDma0QVlX+oVAWj8YP0kuhGH4mGSqTBJfCIF7F1g.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'XXX.XX.XX.XX' (ECDSA) to the list of known hosts.
root@47.94.81.13's password:
Last login: Wed Dec 20 16:59:42 2017

Welcome to Alibaba Cloud Elastic Compute Service !

[root@izsnbdeue3bgqyz ~]#

Java环境

下载jdk，然后复制到服务器中

scp XXXX.tar.gz root@XXX.XX.XX.XX:/usr/bin

解压

tar zxvf XXXX.tar.gz

配置环境变量

vi /etc/profile

添加

export JAVA_HOME=/usr/bin/jdk1.8.0_151

export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar

export PATH=$JAVA_HOME/bin:$PATH

加载设置的变量

source /etc/profile

测试一下：

[root@izsnbdeue3bgqyz ~]# java -version
java version "1.8.0_151"
Java(TM) SE Runtime Environment (build 1.8.0_151-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.151-b12, mixed mode)

处理短时掉线问题

vim /etc/ssh/ssh_config

在里面加入：

TCPKeepAlive yes    
ClientAliveInterval 3  

重启即可

service sshd restart