hostgroup must look like this —>
contactgroup.cfg must look like this—>
and finally the contacts.cfg file—>
also make sure to follow this simple rules ---->
1.Verify that all contacts are a member of at least one contact group.
2.Verify that all contacts specified in each contact group are valid.
3.Verify that all hosts are a member of at least one host group.
4.Verify that all hosts specified in each host group are valid.
5.Verify that all hosts have at least one service associated with them.
6.Verify that all commands used in service and host checks are valid.
7.Verify that all commands used in service and host event handlers are valid.
8.Verify that all commands used in contact service and host notifications are valid.
9Verify that all notification time periods specified for services, hosts, and contact are valid.
10.Verify that all service check time periods specified for services are valid