Several Neutron DHCP servers have the same IP address in Red Hat OpenStack Platform

Issue

• Duplicate IP addresses exist in a qdhcp network namespace across multiple Controller nodes or Network nodes.

  [root@controller-0 ~]# ip netns exec qdhcp-aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa ip a
  800: tapXXXXX-00: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1200 qdisc noqueue state UNKNOWN group default qlen 1000
      link/ether 00:00:00:00:00:aa brd ff:ff:ff:ff:ff:ff
      inet 169.254.169.254/16 brd 169.254.255.255 scope global tapXXXXX-00
         valid_lft forever preferred_lft forever
      inet 10.0.0.1/24 brd 172.17.3.255 scope global tapXXXXX-00 <===============(*)the same IP address
         valid_lft forever preferred_lft forever
  
  [root@controller-1 ~]# ip netns exec qdhcp-aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa ip a
  900: tapYYYYY-00: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1200 qdisc noqueue state UNKNOWN group default qlen 1000
      link/ether 00:00:00:00:00:bb brd ff:ff:ff:ff:ff:ff
      inet 169.254.169.254/16 brd 169.254.255.255 scope global tapYYYYY-00
         valid_lft forever preferred_lft forever
      inet 10.0.0.1/24 brd 172.17.3.255 scope global tapYYYYY-00 <===============(*)the same IP address
         valid_lft forever preferred_lft forever
  

• This cause link flapping on a bridge which connected to the Controller nodes or Network nodes.