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ERROR with installing neutron-server [liberty]

asked 2016-02-12 10:34:16 -0500

malascom gravatar image

updated 2016-02-13 08:20:19 -0500

I folowed the official ( for installing and configuring open stack . When i restart the neutron server and i look at the /var/log/neutron/neutron-server.log i get this error:

ERROR neutron.api.extensions [-] It was impossible to process the following extensions: subnet_allocation because of missing requirements.

Here is my neutron.conf file:


 rpc_backend = rabbit     
auth_strategy= keystone     
my_ip =    
security_group_api = neutron    


     rabbit_host = controller 
     rabbit_userid = openstack 
     rabbit_password =alascom123


connection = mysql+pymysql://nova:alascom@controller/nova


auth_uri = http://controller:5000 
auth_url = http://controller:35357 
auth_plugin = password 
project_domain_id = default 
user_domain_id = default 
project_name = service 
username = nova 
password = alascom


vncserver_listen = vncserver_proxyclient_address =


host = controller


lock_path = /var/lib/nova/tmp


url = http://controller:9696 
auth_url = http://controller:35357 
auth_plugin = password 
project_domain_id = default 
user_domain_id = default 
region_name = RegionOne 
project_name = service 
username = neutron 
password = alascom

service_metadata_proxy = True metadata_proxy_shared_secret = alascom

and here is the plugin.ini

# (ListOpt) List of network type driver entrypoints to be loaded from
# the neutron.ml2.type_drivers namespace.

type_drivers = flat,vlan

# Example: type_drivers = flat,vlan,gre,vxlan,geneve

# (ListOpt) Ordered list of network_types to allocate as tenant
# networks. The default value 'local' is useful for single-box testing
# but provides no connectivity between hosts.

tenant_network_types =

# Example: tenant_network_types = vlan,gre,vxlan,geneve

# (ListOpt) Ordered list of networking mechanism driver entrypoints
# to be loaded from the neutron.ml2.mechanism_drivers namespace.

mechanism_drivers = linuxbridge

# Example: mechanism_drivers = openvswitch,mlnx
# Example: mechanism_drivers = arista
# Example: mechanism_drivers = openvswitch,cisco_nexus,logger
# Example: mechanism_drivers = openvswitch,brocade
# Example: mechanism_drivers = linuxbridge,brocade

# (ListOpt) Ordered list of extension driver entrypoints
# to be loaded from the neutron.ml2.extension_drivers namespace.

extension_drivers = port_security

# Example: extension_drivers = anewextensiondriver

# =========== items for MTU selection and advertisement =============
# (IntOpt) Path MTU.  The maximum permissible size of an unfragmented
# packet travelling from and to addresses where encapsulated Neutron
# traffic is sent.  Drivers calculate maximum viable MTU for
# validating tenant requests based on this value (typically,
# path_mtu - max encap header size).  If <=0, the path MTU is
# indeterminate and no calculation takes place.
# path_mtu = 0

# (IntOpt) Segment MTU.  The maximum permissible size of an
# unfragmented packet travelling a L2 network segment.  If <=0,
# the segment MTU is indeterminate and no calculation takes place.
# segment_mtu = 0

# (ListOpt) Physical network MTUs.  List of mappings of physical
# network to MTU value.  The format of the mapping is
# <physnet>:<mtu val>.  This mapping allows specifying a
# physical network MTU value that differs from the default
## physical_network_mtus =
# Example: physical_network_mtus = physnet1:1550, physnet2:1500
# ======== end of items for MTU selection and advertisement =========

# (StrOpt) Default network type for external networks when no provider
# attributes are specified. By default it is None, which means that if ...
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Please post the neutron configuration files.(neutron.conf and plugin.ini)

pjb gravatar imagepjb ( 2016-02-12 12:16:14 -0500 )edit

i just edit the problem and i add neutron.conf. where can i find plugin.ini ?

in etc/neutron/plugins/ml2/ i have: linuxbridge_agent.ini
sriov_agent.ini ml2_conf_brocade_fi_ni.ini

malascom gravatar imagemalascom ( 2016-02-12 15:53:33 -0500 )edit

plugin.ini will be inside /etc/neutron/ folder. It is basically a soft link to your ml2_conf.ini file. If plugin.ini file is not there, then you need to create it

# ln -s /etc/neutron/plugins/ml2/ml2_conf.ini /etc/neutron/plugin.ini
pjb gravatar imagepjb ( 2016-02-13 00:47:28 -0500 )edit

i created plugin.ini and i added to the problem description . still does not work the subnet extension

malascom gravatar imagemalascom ( 2016-02-13 08:22:28 -0500 )edit

2 answers

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answered 2016-02-15 01:23:47 -0500

pjb gravatar image

updated 2016-02-15 02:40:04 -0500

Hi, add the following configuration value in your neutron.conf file(

core_plugin = ml2
service_plugins = router

Restart all the services,(nova and neutron)

NOTE: The reason of the error is because subnet_allocation extension requires the router service plugin.

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tnx a lot. this fixed the error for me! thanks :D

malascom gravatar imagemalascom ( 2016-02-15 03:29:39 -0500 )edit

Hi, welcome. Can you please mark it as answer. It will be my first. ;)

pjb gravatar imagepjb ( 2016-02-15 05:02:35 -0500 )edit

answered 2016-10-07 00:49:12 -0500

srihitha gravatar image


i am integrating dns with neutron and nova in openstack liberty following this doc (

But in step 2 in this doc where we will provide extension_drivers = port_security,dns in ml2 configuration i am facing issues in neutron server

ERROR neutron.service RuntimeError: Unable to load neutron from configuration file /etc/neutron/api-paste.ini

Not understanding what to do? can some one help me in this aspect?

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Asked: 2016-02-12 10:34:16 -0500

Seen: 5,772 times

Last updated: Oct 07 '16