Our 3 Flannel hosts:
A few setup notes: I haven't looked at this on GCE or AWS. It helps to add the hosts to /etc/hosts, or have some other DNS solution. In my case, I set up these VM's in Vagrant on my laptop and modified /etc/hosts.
Software used on these Fedora hosts.
# rpm -qa | egrep "etc|docker|flannel" flannel-0.2.0-1.fc21.x86_64 docker-io-1.4.0-1.fc21.x86_64 etcd-0.4.6-6.fc21.x86_64
# ip a
# systemctl start etcd; systemctl status etcd