[master] scenario008 multinode job failing at undercloud giving Invalid local_interface specified. br-ex is not available.

tripleo-ci-centos-7-scenario008-multinode-oooq-container job is broken from very long time, is failing
at undercloud install giving following trace back:
http://logs.openstack.org/24/567224/62/check/tripleo-ci-centos-7-scenario008-multinode-oooq-container/92e45e5/logs/undercloud/home/zuul/undercloud_install.log.txt.gz#_2018-07-18_00_24_00

2018-07-18 00:24:00 | 2018-07-18 00:24:00,547 INFO: Logging to /home/zuul/.instack/install-undercloud.log
2018-07-18 00:24:00 | 2018-07-18 00:24:00,596 INFO: Checking for a FQDN hostname...
2018-07-18 00:24:00 | 2018-07-18 00:24:00,666 INFO: Static hostname detected as centos-7-ovh-gra1-0000781434
2018-07-18 00:24:00 | 2018-07-18 00:24:00,695 INFO: Transient hostname detected as centos-7-ovh-gra1-0000781434
2018-07-18 00:24:00 | 2018-07-18 00:24:00,702 ERROR: Undercloud configuration validation failed: Invalid local_interface specified. br-ex is not available.
2018-07-18 00:24:00 | 2018-07-18 00:24:00,703 DEBUG: An exception occurred
2018-07-18 00:24:00 | Traceback (most recent call last):
2018-07-18 00:24:00 | File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 2310, in install
2018-07-18 00:24:00 | _validate_configuration()
2018-07-18 00:24:00 | File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 871, in _validate_configuration
2018-07-18 00:24:00 | _validate_network()
2018-07-18 00:24:00 | File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 793, in _validate_network
2018-07-18 00:24:00 | validator.validate_config(params, error_handler)
2018-07-18 00:24:00 | File "/usr/lib/python2.7/site-packages/instack_undercloud/validator.py", line 43, in validate_config
2018-07-18 00:24:00 | _validate_interface_exists(local_params, error_callback)
2018-07-18 00:24:00 | File "/usr/lib/python2.7/site-packages/instack_undercloud/validator.py", line 194, in _validate_interface_exists
2018-07-18 00:24:00 | error_callback(message)
2018-07-18 00:24:00 | File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 779, in error_handler
2018-07-18 00:24:00 | raise validator.FailedValidation(message)
2018-07-18 00:24:00 | FailedValidation: Invalid local_interface specified. br-ex is not available.
2018-07-18 00:24:00 | 2018-07-18 00:24:00,705 ERROR:

from ODL logs:http://logs.openstack.org/24/567224/62/check/tripleo-ci-centos-7-scenario008-multinode-oooq-container/92e45e5/logs/undercloud/var/log/extra/odl/odl_info.log.txt.gz

+ arp -an
? (147.135.132.1) at 86:0b:9d:c8:6e:a1 [ether] on eth0
+ ip netns list
+ ovs-ofctl -OOpenFlow13 show br-int
/tmp/odl_extra_logs.sh: line 10: ovs-ofctl: command not found
+ ovs-ofctl -OOpenFlow13 dump-flows br-int
/tmp/odl_extra_logs.sh: line 12: ovs-ofctl: command not found
+ ovs-ofctl -OOpenFlow13 dump-groups br-int
/tmp/odl_extra_logs.sh: line 14: ovs-ofctl: command not found
+ ovs-ofctl -OOpenFlow13 dump-group-stats br-int
/tmp/odl_extra_logs.sh: line 16: ovs-ofctl: command not found
+ ovs-vsctl list Open_vSwitch
/tmp/odl_extra_logs.sh: line 18: ovs-vsctl: command not found
+ ovs-vsctl show
/tmp/odl_extra_logs.sh: line 20: ovs-vsctl: command not found

Here is the list of all failed with same error: http://zuul.openstack.org/builds.html?job_name=tripleo-ci-centos-7-scenario008-multinode-oooq-container

There might be something wrong with setting network.