[root@excession:~]systemctl status netfilter-persistent.service
● netfilter-persistent.service - netfilter persistent configuration
   Loaded: loaded (/lib/systemd/system/netfilter-persistent.service; enabled)
   Active: failed (Result: exit-code) since Thu 2019-06-06 19:52:20 EDT; 16min ago
  Process: 30902 ExecStart=/usr/sbin/netfilter-persistent start (code=exited, status=1/FAILURE)
 Main PID: 30902 (code=exited, status=1/FAILURE)

Jun 06 19:52:20 excession.server.gtaxl.net netfilter-persistent[30902]: run-parts: executing /usr/share/netfilter-persistent/plugins.d/15-ip4tables start
Jun 06 19:52:20 excession.server.gtaxl.net netfilter-persistent[30902]: run-parts: /usr/share/netfilter-persistent/plugins.d/15-ip4tables exited with return code 2
Jun 06 19:52:20 excession.server.gtaxl.net netfilter-persistent[30902]: run-parts: executing /usr/share/netfilter-persistent/plugins.d/25-ip6tables start
Jun 06 19:52:20 excession.server.gtaxl.net netfilter-persistent[30902]: Warning: skipping IPv6 (no rules to load)
Jun 06 19:52:20 excession.server.gtaxl.net systemd[1]: netfilter-persistent.service: main process exited, code=exited, status=1/FAILURE
Jun 06 19:52:20 excession.server.gtaxl.net systemd[1]: Failed to start netfilter persistent configuration.
Jun 06 19:52:20 excession.server.gtaxl.net systemd[1]: Unit netfilter-persistent.service entered failed state.