The 30th Linux environment to build the Ethereum POA alliance chain

Operating system: centos_7_06_64

Node version: geth-linux-amd64-1.9.14-6d74d1e5.tar.gz

1. Preparation

(1) Download the geth version of Ethereum from the official website. This article uses geth-linux-amd64-1.9.14-6d74d1e5.tar.gz;

(2) Three cloud servers, this article uses 2 core CPU \ 4G memory \ 40G hard disk \ 1Mbps;

         Use command to view hard disk capacity:

free -mh                   //内存使用情况
fdisk -l                   //硬盘信息
df -h                      //硬盘使用情况
df -aT                     //所有存储系统空间使用情况

(3) Open the corresponding ports of the cloud server, such as 30333, 8545, etc. which will be used later;

         There are three ways to check whether the port is open and whether the host is reachable:

方式一：
yum install -y telnet                                       //安装telnet
telnet [ip] [port]                                          //连接测试
# telnet 172.0.0.1 22
Trying 172.0.0.1...
Connected to 172.0.0.1.                                     //成功
Connection refused                                          //失败
方式二：
yum install -y nc