این مشکلات وجود داره هنگام نصب

کد:
[root@localhost ~]# service postgresql start
Redirecting to /bin/systemctl start postgresql.service
کد:
[root@localhost ~]# service iptables start
Redirecting to /bin/systemctl start iptables.service
Failed to start iptables.service: Unit not found.
کد:
[root@localhost ~]# service postgresql start
Redirecting to /bin/systemctl start postgresql.service
کد:
[root@localhost ~]# service httpd start
Redirecting to /bin/systemctl start httpd.service
کد:
[root@localhost ~]# chkconfig postgresql on
Note: Forwarding request to 'systemctl enable postgresql.service'.
کد:
[root@localhost ~]# chkconfig httpd on
Note: Forwarding request to 'systemctl enable httpd.service'.