HTTP error

I am newbie to nagios, I have configured nagios to monitor local host sewrvice.
I have installed nagios 3.0b7 thru Fedora quickstart guide & followed the instruction .
The plugin version is nagios-plugins 1.4.7
But I am facing problem with http . when I run following command
#./check_http -H localhost -v
I get the follwing error
GET / HTTP/1.0
User-Agent: check_http/1.101 (nagios-plugins 1.4.7)
Host: localhost

localhost:80/ is 574 characters
STATUS: HTTP/1.1 403 Forbidden
**** HEADER ****
Date: Thu, 20 Dec 2007 09:32:35 GMT
Server: Apache/2.2.3 (CentOS)
Content-Length: 395
Connection: close
Content-Type: text/html; charset=iso-8859-1
**** CONTENT ****

403 Forbidden

Forbidden

You don't have permission to access / on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.


Apache/2.2.3 (CentOS) Server at localhost Port 80

HTTP WARNING: HTTP/1.1 403 Forbidden

After googling for the problem I found This may be happening due to permission isue
so I amde apache a nagios grup member
#usermod -G nagios apache
Hereis the directory permission of
drwxrwsr-x 2 nagios nagios 4096 Dec 20 14:57 /usr/local/nagios/var/rw
prw-rw---- 1 nagios nagios 0 Dec 20 15:01 nagios.cmd
Please help me.
Thanks
Vinod

It’s because you’re using default url path which is /

You should use the -u option with the command relative to your path to web site you’re trying to reach on your localhost. For example, if you’re trying to access Nagios web interface on your localhost and you’ve set it to be on the localhost/nagios you have to put
-u nagios
Then you will get HTTP warning 401 unauthorized which you can ignore because you can now see that you’re reaching http service on localhost but you’re unauthorized. Add the
-e HTTP/1.0 401
to get OK status