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I have installed openstack grizzly with quantum. The openstack is installed on single virtual machine using vmware.

First i have created external network, router and security group using following command

quantum net-create public --router:external=True

Then i added my external network subnet (ip pool not used in external network)

Then i created router

Then i set my router gateway to external network

I created security group to allow ssh and icmp.

On second step i created private network with dhcp enabled

Then created router interface and attach it to my private network

On third step i executed following command

iptables -A POSTROUTING -t mangle -p udp --dport 68 -j CHECKSUM --checksum-fill

On fourth step i launched the instance with private network

On fifth step i generated floating ip of external network and associates it to instance

Problem Statement:

VM instances are not getting ip addresses from dhcp.

If i configure ip addresses manually (private network) the VM instances can ping each other.

After manual configuration there is no internet on VM's and they cannot ping any external network device.

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