ENI and public IP address

Hello Gustavomanoel,

I will answer your questions below.

Question 1 - 'If I shutdown my instance, will the Public address change?'
Answer: Yes. We release your instance's public IP address when it is stopped or terminated. Your stopped instance receives a new public IP address when it is restarted. [1]

Question 2 - 'If I detach the ENI of my instance, will the public address be released?'
Answer: Is this the default primary network interface (eth0) of your instance? If yes, then please note that you cannot detach a primary network interface from an instance. [2].

I hope that you find this information helpful. Please let us know if you need any further help.

Links:
[1] https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-instance-addressing.html#concepts-public-addresses
[2] https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-eni.html#eni-basics

Regards,
awstomas

Hello awstomas,

As expected...
Yes, it is the primary network interface.
Thank you very much for you support.

Regards,
Gustavo Manoel