Send a request on the EC2 instance: http://169.254.169.254/latest/meta-data/public-ipv4
curl http://169.254.169.254/latest/meta-data/local-ipv4
curl http://169.254.169.254/latest/meta-data/public-ipv4
curl http://169.254.169.254/latest/meta-data/public-hostname
For details, please see: https://blog.csdn.net/Swallow_he/article/details/105711779