Route Public IPv4 Address within VPC

Question

A customer wants to route one specific IPv4 address (which is an EIP of another EC2 instance) within a VPC, but different subnet. Is this possible? 
Setting up an entry in the 2 route tables does not seem to work.
Ping via private IP works, but not public IP.

Route Table 1:

- 172.31/16 local
 - 0.0.0.0/0 igw
 - 1.1.1.1/32 TargetInstance

Route Table 2:

- 172.31/16 local
 - 0.0.0.0/0 igw
 - 2.2.2.2/32 SourceInstance

Accepted Answer

You can do that, but you will need to [disable source/destination checking][1]:

> Source/destination checking
> 
> Disabling source/destination checking enables an instance to handle
> network traffic that isn't specifically destined for the instance. For
> example, instances running services such as network address
> translation, routing, or a firewall should disable the
> source/destination check attribute. This attribute is enabled by
> default

[1]: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-eni.html

Route Public IPv4 Address within VPC

Relevanter Inhalt