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Openstack : Fixing Failed to create network. No tenant network is available for allocation issue.

Assumptions:
  • You are using ML2 plugin configured to use Vlans

If you try to create a network for a tenant and it fails with the following error:

Error: Failed to create network "Test": 503-{u'NeutronError': {u'message': u'Unable to create the network. No tenant network is available for allocation.', u'type': u'NoNetworkAvailable', u'detail': u''}}

The problem can be due to missing configuration in the below files:

In /etc/neutron/plugins/ml2/ml2_conf.ini
network_vlan_ranges =physnet1:1000:2999 (1000:2999 is the Vlan range allocation)

In /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini
bridge_mappings = physnet1:br-eth1 (in OVS we map the physical network to the OVS bridge)

Note
  1. You should have created a bridge br-eth1 manually and mapped it to a port
    • ovs-vsctl add-br br-eth1
    • ovs-vsctl add-port br-eth1 eth1
Once configuration is done, restart the neutron ovs agent on the compute node(s):
  • service neutron-openvswitch-agent restart
In the case of Juniper's Openstack ML2 plugin, we will need to supply the mapping between physical network and the port that it uses via the following command:

  •  jnpr_nic_mapping add -H host_name -b bridge_name -n nic
An example entry would be jnpr_nic_mapping add -H 10.20.30.40 -b physnet1 -n eth1

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openstack failed to create network

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