EC2 instances cannot ping each other

Question

I have 2 EC2 Ubuntu instances. They are sharing same VPC, subnet and Security Group. Instances' firewall was turnoff. But I still can't ping each other by private IP. How to allow those instances ping each other?

Answer 1

You have to add a rule in the security group for that. Add "custom ICMP" rule for "Echo Request" or "ALL ICMP Traffic" and as the source IP, add the security group's identifier (looks something like: sg-xxxxxxxx)