Created attachment 1324244 [details] engine and ovirt-provider-ovn logs Description of problem: When creating OVN subnet without specifying a DNS server or gateway, OVN throws a generic error in the UI: "Error while executing action Add Subnet to Provider: Failed to communicate with the external provider, see log for additional details.", and the provider doesn't handle the case, and throws an exception: Traceback (most recent call last): File "/usr/share/ovirt-provider-ovn/handlers/base_handler.py", line 111, in _handle_request method, key, id, content) File "/usr/share/ovirt-provider-ovn/handlers/selecting_handler.py", line 53, in handle_request self._get_response_handler(method, key), content, id File "/usr/share/ovirt-provider-ovn/handlers/neutron.py", line 36, in call_response_handler return response_handler(ovn_north, content, id) File "/usr/share/ovirt-provider-ovn/handlers/neutron_responses.py", line 143, in post_subnets subnet = nb_db.add_subnet(received_subnet) File "/usr/share/ovirt-provider-ovn/ovndb/ovn_north_mappers.py", line 58, in wrapper else f(wrapped_self, rest_data)) File "/usr/share/ovirt-provider-ovn/ovndb/ovn_north_mappers.py", line 41, in wrapper return cls.rest2row(wrapped_self, f, rest_data, entity_id) File "/usr/share/ovirt-provider-ovn/ovndb/ovn_north_mappers.py", line 272, in rest2row if SubnetMapper.REST_SUBNET_DNS_NAMESERVERS in rest_data IndexError: list index out of range Version-Release number of selected component (if applicable): ovirt-provider-ovn-1.1-2.20170905145914.gitaf4fe87.el7.centos.noarch How reproducible: 100% Steps to Reproduce: 1. Create OVN network with subnet, specify CIDR, and don't specify gateway or DNS server. Actual results: UI throws error, ovirt-provider-ovn throws exception. Expected results: UI should display a guided message to the user, for example, "DNS / gateway is required in order to create a subnet". ovirt-provider-ovn should handle this and log similar message.
Verified on: 4.2.0-0.0.master.20170924221426.git196b802.el7.centos
This bugzilla is included in oVirt 4.2.0 release, published on Dec 20th 2017. Since the problem described in this bug report should be resolved in oVirt 4.2.0 release, published on Dec 20th 2017, it has been closed with a resolution of CURRENT RELEASE. If the solution does not work for you, please open a new bug report.