Host Down

Paul L. Allen pla at softflare.com
Thu Jan 22 23:43:34 CET 2004


Gerald Wichmann writes: 

> Needless to say if I manually run check_host_alive according to 
> checkcommand.cfg from the distributed nagios server that monitors the
> new hosts I've added it comes back as the host being OK.

No, it wasn't needless to say, because you asked for information on how
to troubleshoot the problem.  Since you didn't say you'd manually run
check_host_alive, which is the very first stage in troubleshooting, I
pointed you in that direction. 

I'd guess a high proportion of problems with hosts being reported down
are because either the host is not pingable from the nagios server
(router or firewall blocking pings) or because somebody has redefined
check_host_alive to be something silly.  So checking this really is the
very first stage in determining what might be wrong and your post did
not say you'd eliminated that as the cause.  Sad to say, a lot of posts
here indicate that a manual check_host_alive is not something that
many people would think to perform (or reading the documentation, for
that matter). 

> There's something going on here I'm just not catching.

Are there any services down on the host that is shown as down?  My
understanding is that as soon as a service is reported as down Nagios
performs a host test on the basis that the host could have died but it
won't immediately know that all services on the host are down because
their checks could be 5 or 10 minutes away.  An immediate host test is
a fast way of finding out if it's a service failure or a host failure. 

That still doesn't explain your problem, if your manual check_host_alive
test actually worked for the host.  Have you checked very carefully
that what you are doing manually really is what your configuration
causes to happen on a check_host_alive?  Are you manually using an
IP address where your configuration uses a domain name or vice versa?
Did you run that check from the nagios server itself or from another
machine? 

-- 
Paul Allen
Softflare Support 




-------------------------------------------------------
The SF.Net email is sponsored by EclipseCon 2004
Premiere Conference on Open Tools Development and Integration
See the breadth of Eclipse activity. February 3-5 in Anaheim, CA.
http://www.eclipsecon.org/osdn
_______________________________________________
Nagios-users mailing list
Nagios-users at lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nagios-users
::: Please include Nagios version, plugin version (-v) and OS when reporting any issue. 
::: Messages without supporting info will risk being sent to /dev/null





More information about the Users mailing list