There are some issues for subnet DHCP updating, both in DHCPv4 and DHCPv6.
Issue 1:
Create a subnet with DHCP disabled, then create a VM, then enable subnet DHCP.
Result is, dhcpv4_options/dhcpv6_options was not set[1], VM can not get a IP, unless restarting the VM.
Issue 2:
Create a subnet with DHCP disabled, then create a Port with DHCP extra_dhcp_opts, then enable subnet DHCP.
Result is, DHCP_Options row for this port was not created.
Issue 3:
Create a subnet with DHCP enabled, then create a Port, then disable subnet DHCP.
Result is, DHCP_Options row was not deleted, only options was cleared, this row turned to incomplete, a lot of error logs print in ovn-northd.log[2].
[1]
DHCP_Options table
_uuid cidr external_ids options
------------------------------------ -------------- -------------------------------------------------- -----------------------------------------------------------------------------------------------------------
51900184-d804-40de-a3b6-a3656c8f1136 "10.0.0.64/26" {subnet_id="14e35811-7aef-4c27-a893-820bb4a22c7f"} {lease_time="43200", mtu="1442", router="10.0.0.65", server_id="10.0.0.65", server_mac="fa:16:3e:0c:33:d2"}
Logical_Switch_Port table
_uuid addresses dhcpv4_options dhcpv6_options dynamic_addresses enabled external_ids name options parent_name port_security tag tag_request type up
------------------------------------ ------------------------------- -------------- -------------- ----------------- ------- ------------------------ ---------------------------------------------- -------------------------------------------------------- ----------- ------------------------------- --- ----------- -------- -----
02ddbb1d-2fec-4ed9-bc4d-eff459d622a2 ["fa:16:3e:b2:e3:dd 10.0.0.75"] [] [] [] true {"neutron:port_name"=""} "482eebc7-4437-4f61-9a81-24327015b942" {} [] ["fa:16:3e:b2:e3:dd 10.0.0.75"] [] [] "" true
[2]
|ovn_northd|WARN|Required DHCPv4 options not defined for lport - "482eebc7-4437-4f61-9a81-24327015b94
Fix proposed to branch: master
Review: https:/