wget https://install.direct/go.sh

sudo bash go.sh

record PORT and UUID

sudo nano /etc/v2ray/config.json

{
  "inbounds": [
    {
      "port": 40827,
      "protocol": "vmess",
      "settings": {
        "clients": [
          {
            "id": "505f001d-4aa8-4519-9c54-6b65749ee3fb",
            "alterId": 64
          }
        ]
      },
      "streamSettings": {
        "network": "mkcp",
        "kcpSettings": {
          "uplinkCapacity": 5,
          "downlinkCapacity": 100,
          "congestion": true,
          "header": {
            "type": "none"
          }
        }
      }
    }
  ],
  "outbounds": [
    {
      "protocol": "freedom",
      "settings": {}
    }
  ]
}

firewall-cmd --zone=public --add-port=40827/udp --permanent
firewall-cmd --reload

sudo /etc/init.d/v2ray restart

Auto run 

sudo nano /etc/rc.local

add 

sudo /etc/init.d/v2ray restart

Client

https://github.com/2dust/v2rayN/releases

network:kcp