Use User and Group variables instead of sudo

use User and Group in octavia-interface service.
this way looks more graceful

this change also fix the octavia-interface does not restart
when the octavia-interface.service changed.

Change-Id: I9d253d7519b1774985d165a080047fdbecd321b4

ansible/roles/octavia/tasks/hm-interface.yml

@@ -67,11 +67,12 @@
     dest: /etc/systemd/system/octavia-interface.service
   register: octavia_interface
 
-- name: Reload octavia-interface.service if required
+- name: Restart octavia-interface.service if required
   become: True
   systemd:
     name: octavia-interface
     daemon_reload: yes
+    state: restarted
   when: octavia_interface.changed
 
 - name: Enable and start octavia-interface.service

ansible/roles/octavia/templates/octavia-interface.service.j2

@@ -5,10 +5,12 @@ After=docker.service
 
 [Service]
 Type=oneshot
+User=root
+Group=root
 RemainAfterExit=true
-ExecStartPre=/usr/bin/sudo /sbin/ip link set dev {{ octavia_network_interface }} address {{ port_info.port.mac_address }}
-ExecStart=/usr/bin/sudo /sbin/dhclient -v {{ octavia_network_interface }} -cf /etc/dhcp/octavia-dhclient.conf
-ExecStop=/usr/bin/sudo /sbin/dhclient -r {{ octavia_network_interface }}
+ExecStartPre=/sbin/ip link set dev {{ octavia_network_interface }} address {{ port_info.port.mac_address }}
+ExecStart=/sbin/dhclient -v {{ octavia_network_interface }} -cf /etc/dhcp/octavia-dhclient.conf
+ExecStop=/sbin/dhclient -r {{ octavia_network_interface }}
 
 [Install]
 WantedBy=multi-user.target