NetworkManager dispatcher scripts 30-static-dhcp and 30-static-dhcpv6 modify the NetworkManager connection of the OVS interface ovs-if-br-ex in case of a infinite DHCP lease: They will change ipv4.method and ipv6.method from auto to manual in order to statically assign DHCP addresses etc.

The purpose of this feature was to enable nodes to keep their network configuration and network connectivity when their DHCP server becomes unavailable for any reason. For example, this allowed users to deploy OpenShift nodes with "static" ip addresses, i.e. ip addresses with infitite DHCP leases, using an initial DHCP server that would then be removed once the cluster is up.

However, the changes by the dispatcher scripts to NM connection ovs-if-br-ex were saved to disk which conflicts with the rollback behaviour of configure-ovs.sh (ovs-configuration.service): OVN-Kubernetes configuration is rolled back and (re)generated on every boot, to take in account any changes that have possibly been applied in the standard configuration sources. In OpenShift releases without PR #4877, the NM connection file for ovs-if-br-ex in /etc/NetworkManager/system-connections will not be removed during rollback which causes conflicts when changes have been applied in the standard configuration sources. With PR #4877, the NM connection file is removed during rollback, defeating the purpose of this feature.

Nowadays, OpenShift has proper support for static ip addresses built-in and this inf-lease-to-static feature has not been documented since 4.9. Both dispatcher scripts were only kept due to the "no breaking changes" policy in OpenShift. However, because of the conflict with configure-ovs.sh's rollback feature, those dispatcher scripts should finally be removed.