This is access from WITHIN an EC2 outbound to anywhere. (EC2-BAD)

I can get INTO the instance via ssh and I can run my webserver on port 80 and I can ping from another EC2 (EC2-GOOD) in the same VPC. The latter EC2-GOOD is the instance I cloned.

Ping to EC2-GOOD from EC2-BAD using local ip address does not work. Nor of course to anywhere I try like github.com.

The security group allows all outbound traffic everywhere.

I temporarily modified the SG to allow all inbound traffic from everywhere. That then allowed ping to EC2-GOOD instance in same VPC via private ip address. public address still failed.

EC2-BAD is an image of EC2-GOOD. The same SG is used on both EC2-BAD and EC2-GOOD. Same VPC, same subnet.

Its an 'exact copy', what can possibly be different?

Thanks for your consideration.

Security group. sg-1e749271 is itself.

SSH TCP 22 sg-1e749271 (linux-securitygroup) RDP TCP 3389

HTTPS TCP 443 sg-1e749271 (linux-securitygroup)

Custom TCP Rule TCP 4545


Custom TCP Rule TCP 4545 sg-1e749271 (linux-securitygroup)


TCP 3306 sg-1e749271 (linux-securitygroup)


HTTP TCP 80 sg-1e749271 (linux-securitygroup)

  • Could you add the security group rules to the question? Also, does EC2-GOOD have an extra security group that EC2-BAD doesn't? – Ladadadada Jul 18 '14 at 7:44
  • 3
    Have you assigned an EIP to BAD? – EEAA Jul 18 '14 at 11:49
  • 1
    Yes, you will likely need to add an Elastic IP to this instance before you can get connectivity. – Kevin Jul 20 '14 at 23:58
  • I have connectivity INTO the instance. E.g. I can ssh and http to it. I just can't do anything OUT of it. That is, I ssh in and then try and ping github.com and it fails. – RobG Jul 21 '14 at 0:46
  • Note that even though I asked for a public DNS, it is blank in the console. Also I added an ENI to which is associated the EIP. Is it that I need to attach the EIP to the EC2 rather than the ENI? – RobG Jul 21 '14 at 0:51

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