Restarting octavia breaks IPv4 Load Balancers with health checks

[alisafari]

After implementing IPv6 health check support in change #919229 for the ovn-octavia-provider, it appears that the maintenance task is inadvertently deleting the `ip_port_mappings` of IPv4 load balancers. This issue results in the load balancers ceasing to function upon the restart of Octavia.

I found this as a potential fix for this issue: [Proposed Fix](https://review.opendev.org/c/openstack/ovn-octavia-provider/+/923196).

[yatin (yatinkarel)]

Thanks alisafari for the bug report, seems you meant https://review.opendev.org/c/openstack/ovn-octavia-provider/+/911413 instead of #919229 as 911413 introduced the clearing of mappings?

[yatin (yatinkarel)]

Assigned to Pavlo Shchelokovskyy considering the mentioned potential fix, if untrue can be updated.

[Fernando Royo (froyoredhat)]

I will check during this afternoon the mentioned issue here, because branch https://review.opendev.org/c/openstack/ovn-octavia-provider/+/923196/1/ovn_octavia_provider/maintenance.py#149 should be don't make any change on a IPv4 LB... I will update here as soon I have tested.