Certbot申请ssl证书
Certbot申请ssl证书先DNS解析环境安装安装epelyum install epel-release安装snapdyum install snapd启用snapd.socketsystemctl enable --now snapd.socket创建/var/lib/snapd/snap和/
Centos7配置ipv6
nano /etc/sysconfig/networkNETWORKING_IPV6=yes 打开IPv6IPV6_AUTOCONF=no 不自动获取地址，即：设置"no”nano /etc/sysconfig/network-scripts/ifcfg-eth0IPV6I
