[Nagiosplug-help] newbie - hosts are down

[Mott Leroy]

Sorry, first time post and am still in the process of learning a bit.

I am running Nagios 2.0b3.
Plugins version: 1.4.
OS: redhat linux (fedora core 2)

Nagios is reporting that all my defined hosts are down. Not sure why 
this is, since they are not in fact down.

I have about 8 hosts that are defined as "inherited" from a generic host.

The generic host is defined as:

define host{
         name     			generic-host
         notifications_enabled    	1
         event_handler_enabled           1
         flap_detection_enabled          1
         failure_prediction_enabled      1
         process_perf_data               1
         retain_status_information       1
         retain_nonstatus_information    1
         check_command                   check-host-alive
         max_check_attempts              10
         notification_interval           120
         notification_period             24x7
         notification_options            d,u,r
         contact_groups                  admins
         register                        0
         }

# "real" hosts defined as:

define host{
         use                     generic-host
         host_name               lieb
         alias                   lieb
         address                 10.0.0.100
         }

And that's about it.

One thing I noticed is that the command listed on the nagios admin under 
"Status Information":

/bin/ping -n -U -w 10 -c 1 10.0.0.104

Works fine on the command line as "root":

[root at haven:~] $ /bin/ping -n -U -w 10 -c 1 10.0.0.104
PING 10.0.0.104 (10.0.0.104) 56(84) bytes of data.
64 bytes from 10.0.0.104: icmp_seq=0 ttl=64 time=0.236 ms

--- 10.0.0.104 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.236/0.236/0.236/0.000 ms, pipe 2
[root at haven:~] $

Run as "nagios", however, it does not work:

[root at haven:~] $ su nagios
[nagios at haven:/root] $ /bin/ping -n -U -w 10 -c 1 10.0.0.104
ping: icmp open socket: Operation not permitted
[nagios at haven:/root] $


Is this the source of the problem?

Any help would be much appreciated. Thanks.