7.10. Known firewall issue

To avoid breaking traffic flows with a firewall reload or restart, run firewall commands before starting Red Hat Enterprise Linux (RHEL). The CNI driver in MicroShift makes use of iptable rules for some traffic flows, such as those using the NodePort service. The iptable rules are generated and inserted by the CNI driver, but are deleted when the firewall reloads or restarts. The absence of the iptable rules breaks traffic flows. If firewall commands have to run after MicroShift is started, manually restart ovnkube-master pod in the openshift-ovn-kubernetes namespace to reset the rules controlled by the CNI driver.