Nagios Support Forum

Hi,

I have installed Nagios XI on VMWare ESXI, when running Autodiscovery it find a wide range of IPs in the network but it's not able to resolve the DNS host name. I chose from the drop-down menu in the wizard DNS Names rather than IP Addresses but in the next page it only shows the IP address as Host Name.

I've configured network IP & DNS name via system--config-network and can ping google.com properly. nslookup resolved the name as well. but Nagios can't resolve the hostname.

What could be the issue?

Thank you

One thing I can think of is do you have reverse DNS setup for the IP's in the range you are scanning, and does your server know about the DNS server that hosts that reverse DNS.

Many times we scan local ranges of IP addresses (e.g. 192.168.x.x) but only have DNS setup for to wider internet.

Can you do a nslookup of an IP address in the range you are scanning from the nagios XI server?

e.g.

Thanks for the help.
Yes the issue was coming from missing reverse DNS zone in the AD, after adding that, Nagios resolved Host name successfully.

Now the issue is something different, in Auto discovery after resolving the names and click on submit it gets stuck in the "Waiting for configuration " and does not go through.

Can you run the following command from the CLI of your Nagios XI machine: Then try to apply the configuration from the GUI, and share anything that the previous command outputs?

Yep I ran the command and saw the error WGET Fails with message "Unable to resolve host address"

I goggled that and found the solution in https://support.nagios.com/kb/print.php?id=532 and it was fixed after adding localhost into the hosts file. Now Autodiscovery resolves the names properly.

Thank you very much for the help.

Thanks for the update. Is it okay to lock the thread?

cdienger wrote:Thanks for the update. Is it okay to lock the thread?

Yes sure..