I was trying to work with Oracle AMIs on Amazon cloud (EC2 instances).
1) Created 2 EC2 instances of an Oracle database AMI ( based on Oracle Enterprise Linux (OEL) 5)
2) I have opened ports in my security group associated with these EC2 instances.
i) TCP 22 (SSH) - 0.0.0.0/0 ( Everybody)
ii) ICMP ALL - 10.0.0.0/8 ( To enable ping functionality)
So i am able to ping successfully from one EC2 to another with the public DNS, but ssh hangs
a) Login to EC2 instance #1 from my desktop - SUCCESS b) ssh public_ip_of_instance_2 22 (HANGS).....
c) Login to EC2 instance #2 from my desktop - SUCCESS d) ssh public_ip_of_instance_1 22 (HANGS).....
Any ideas ? I worked with a default UBUNTU ec2 instance in amazon (public AMIs) and i did not face any problem doing an ssh from one EC2 to another.
Is there something inside OEL (Oracle Enterprise Linux) that locks down ssh on port 22 from one instance to another ?