I just verified both through documentation and by running glusterfs 3.1.2 in the 'default' security group and a non-'default' security group that the ec2 internal network is open by default only within the 'default' security group. Using any other security group you must define your own access rules both for internal and external group access. You can find the information here: http://docs.amazonwebservices.com/AWSEC2/latest/DeveloperGuide/index.html?concepts-security.html Regards, Gerry
