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I'm not sure if this is how VPC EC2 private addresses are supposed to work.

I have two instances in VPC each are allowed to talk to each other (security group), and each instance has two network interfaces. One out of the Two instances have Elastic IP set up and working fine.

The instances can ping and communicate with each other using the private ip that does not have an elastic IP assigned. But when i try to connect/ping with the private IP that does have an elastic IP on it the request times out.

Instances are Ubuntu 12.04 x64

share|improve this question
The rules in a Security Group don't apply to instances, they apply to IP addresses (and ports). What exactly does your Security Group allow? – Ladadadada Feb 23 '13 at 22:19
Communication between the two of all ports. The private ip that does not have a elastic ip can communicate fine its but when I try to use the private ip that does have an elastic ip can not connect from the other instance. – joebl86 Feb 24 '13 at 1:34

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