Monitoramento HTTP no Nagios Core

Estou tentando adicionar um host ao meu servidor Nagios Core se ele verifica sua disponibilidade da mesma forma que você verifica no Nagios XI, então crio meu .cfgarquivo, adiciono as informações do host e tento verificar o arquivo .cfg, mas a cada sempre que executo /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfgrecebo o seguinte erro:

Website: https://www.nagios.org
Reading configuration data...
   Read main config file okay...
Error: Invalid max_check_attempts value for host 'myhost.com'
Error: Could not register host (config file '/usr/local/nagios/etc/objects/webpages.cfg', starting on line 7)
   Error processing object config files!


***> One or more problems were encountered while processing the config files...

     Check your configuration file(s) to ensure that they contain valid
     directives and data definitions.  If you are upgrading from a previous
     version of Nagios, you should be aware that some variables/definitions
     may have been removed or modified in this version.  Make sure to read
     the HTML documentation regarding the config files, as well as the
     'Whats New' section to find out what has changed.

meu webpages.cfgarquivo está assim:

#########################################
#                                       #
#                Hosts                  #
#                                       #
#########################################

define host {
        use             generic-host
        host_name       myhost.com
        alias           myhost
        check_interval  1
        address         xxx.xxx.xxx.xxx
}

#########################################
#                                       #
#               Services                #
#                                       #
#########################################
define service {
            host_name                       myhost.com
            service_description             URL: myhost.com
            check_command                   check_http_url!http://myhost.com
            max_check_attempts              5
            check_interval                  3
            retry_interval                  1
            check_period                    24x7