View FAQ

[ Return To FAQ Index | Search The FAQs ]

FAQ Database : Nagios : Notifications

Title:Notifications about hosts being DOWN or UNREACHABLE when they are UP
FAQ ID:F0016
Submitted By:Ethan Galstad 
Last Updated:07/24/2002


User is receiving notifications about hosts being in certain states (i.e. DOWN or UNREACHABLE), when they are really in a different state (i.e. UP).

This seems to be one of the most common problems for new user of Nagios. Most all of the time this problem is due to an incorrect command definition for the host check command you specified in the host definition.



Make sure that the host check command in your host definition is configured correctly. The host check command is not a service - it is part of the host definition. Also, the host check command is not executed at regular intervals like a service is. Rather, it is executed only when Nagios finds it necessary to check the status of the host.

Important! Just because you have a service that is monitoring ping statistics for a host does not mean that the actual host status is being checked. The status of a host is only checked when a service check results in a non-OK state or if the host was previously down and a service check results in an OK state.

Some symptoms of incorrect host check commands include:

  1. Hosts incorrectly being listed as DOWN
  2. Hosts incorrectly being listed as UNREACHABLE
  3. Alternating alerts/notifications about host problems and recoveries


Related FAQs:
F0015Hosts are incorrectly listed as being DOWN or UNREACHABLE
Keywords:host down unreachable up incorrect wrong notification