service enable slapd enable: unrecognized service

Problem: 

[root@linuxOS cn=config]# service start slapd
start: unrecognized service

[root@linuxOS cn=config]# start slapd
start: Unknown job: slapd

[root@linuxOS cn=config]# start slapd
start: Unknown job: slapd

Solution:
 Use the start command after ServiceName

Syntax :
# service ServiceName Start

[root@linuxOS app]# service slapd start

Checking configuration files for slapd:                    [WARNING]
57e427f1 ldif_read_file: checksum error on "/etc/openldap/slapd.d/cn=config/olcDatabase={1}monitor.ldif"
57e427f1 ldif_read_file: checksum error on "/etc/openldap/slapd.d/cn=config/olcDatabase={2}bdb.ldif"
config file testing succeeded
Starting slapd:                                            [  OK  ]