I wasn't able to ping to my ec2 server although I've done the following command: ec2-authorize default -P icmp -t -1:-1 -s 0.0.0.0/0 when I try this again it gives me: Client.InvalidPermission.Duplicate: The permission '0.0.0.0/0-3--1--1' has already been authorized on the specified group now when I ping from my laptop it gives me: PING 54.251.103.225 (54.251.103.225): 56 data bytes Request timeout for icmp_seq 0 Request timeout for icmp_seq 1 Request timeout for icmp_seq 2 Request timeout for icmp_seq 3 any idea on what to try on next?