Comment 45 for bug 1443798

Hi Neutron-team-members.

I'm Yushiro Furukawa co-worker of Watanabe Isao.
I found that it still reproduce following operations.

So, as soon as possible, I will fix the patch, and post on gerrit.

  solution A: Add validation of allocation_pools when create/update subnet
  solution B: When delete-port, non-admin user can not delete DHCP-port
              (DHCP-port means port attribute "device_owner" is "network:dhcp")

[Operations]
A. Specify "[]"(empty list) at "allocation_pools" when create/update-subnet
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$ $ curl -X POST -d '{"subnet": {"name": "test_subnet", "cidr": "192.168.200.0/24", "ip_version": 4, "network_id": "649c5531-338e-42b5-a2d1-4d49140deb02", "allocation_pools": []}}' -H "x-auth-token:$TOKEN" -H "content-type:application/json" http://127.0.0.1:9696/v2.0/subnets

Then, the dhcp-agent creates own DHCP-port, it is reproduced resync bug.

B. Create port and exhaust allocation_pools
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1. Create subnet with 192.168.1.0/24. And, DHCP-port has alteady created.
   gateway_ip: 192.168.1.1
   DHCP-port: 192.168.1.2
   allocation_pools{"start": 192.168.1.2, "end": 192.168.1.254}
   the number of availability ip_addresses is 252.

2. Create non-dhcp port and exhaust ip_addresses in allocation_pools
   In this case, user creates a port 252 times.
   the number of availability ip_addresses is 0.

3. User deletes the DHCP-port(192.168.1.2)
   the number of availability ip_addresses is 1.

4. User creates a non-dhcp port.
   the number of availability ports are 0.
   Then, dhcp-agent tries to create DHCP-port. It is reproduced resync bug.