大家帮我看看nagios的问题吧

安装配置完nagios后，运行/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg后出现了下面的问题：
Reading configuration data...

Error: Command 'check-host-alive' has already been defined
Error: Could not register command (config file '/usr/local/nagios/etc/commands.cfg', starting on line 181)

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

Check your configuration file(s) to ensure that they contain valid
directives and data defintions. 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.

大家帮忙看看吧