Change public IP address of EC2 instance without stop/start or elastic IP

Question

I\'m running an ubuntu AMI on EC2. Is it possible to assign/request a new public IP address for a running EC2 instance without terminating it and starting it again? Note tha

Answer 1

Reboot does not change your IP

If you reboot your instance from within the EC2 Ubuntu machine, e.g. typing

$ reboot

then your instance will keep the same internal and public IP.

Stopping the instance does change your IP

If you use your AWS EC2 management console and stop your machine (don't terminate it!), you give up the assigned IP addresses.

You will request a new address if you start the instance again.

How to quickly check your IP

You can check for your public and private IPs using CURL or Perl GET, install

$ sudo apt-get install libwww-perl

Now type for internal:

$ GET http://169.254.169.254/latest/meta-data/local-ipv4; echo
172.31.44.114

Or for public:

$ GET http://169.254.169.254/latest/meta-data/public-ipv4; echo
54.72.253.107

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