For the above issue, there may be multiple cause of creating network.
1. Check the neutron port is open in firewall or not. If it is not, use the below command to open this.
$ iptables -A INPUT -p tcp –dport 9696 -j ACCEPT
$netstat -lnpt | grep 9696
2. After that check keystone section in /etc/neutron/neutron.conf file.
3. Check the neutron services are running or not.
$ neutron net-list
4. If there is not error logs in /etc/log/neutron, but there is issue in service communication.
$ service neutron-server restart
5. If you are still facing the same issue, Now try to create the network in debug mode to trace out.
$ openstack –debug network create net1
Hope this will solve your problem.