Unable to monitor windows DHCP server in nagiosXI

[dca_admin]

Hello Team,

We are trying to monitor the Windows DHCP server in NagiosXI. But we are getting an error called error: CRITICAL No DHCPOFFERS were received.
Please check below running commands and screenshot.

First let you know one more thing by default dhcp port numbers is 67&68. But here in local environment dhcp port is assigned "49153(TCP)". Is there any chance to change the port numbers in "check_dhcp" nagios plugin.

Running Commands:
# su - nagios
# /usr/local/nagios/libexec/check_dhcp -v -i ens192
Output: OK: Received 1 DHCPOFFER(s), max lease time = 0 sec.
# /usr/local/nagios/libexec/check_dhcp -v -i ens192 -s <DHCP Server IP>
Error: CRITICAL: No DHCPOFFERs were received.
I tried with custom port number: # /usr/local/nagios/libexec/check_dhcp -v -i ens192 -s <DHCP Server IP> -p 49153
No Output.

Pls, help us to solve this issue. Its windows DHCP server.

[scottwilkerson]

It looks like someone else from your company recently asked the same question which was answered here
https://support.nagios.com/forum/viewto ... 20#p287447

There is no option in the check_dhcp plugin to pass a custom port... I don't see a "-p" option in the usage.

/usr/local/nagios/libexec/check_dhcp -h
check_dhcp v2.2.1 (nagios-plugins 2.2.1)
Copyright (c) 2001-2004 Ethan Galstad ([email protected])
Copyright (c) 2001-2007 Nagios Plugin Development Team
<[email protected]>

This plugin tests the availability of DHCP servers on a network.


Usage:
check_dhcp [-v] [-u] [-s serverip] [-r requestedip] [-t timeout]
[-i interface] [-m mac]

Options:
-h, --help
Print detailed help screen
-V, --version
Print version information
--extra-opts=[section][@file]
Read options from an ini file. See
https://www.nagios-plugins.org/doc/extra-opts.html
for usage and examples.
-v, --verbose
Show details for command-line debugging (Nagios may truncate output)
-s, --serverip=IPADDRESS
IP address of DHCP server that we must hear from
-r, --requestedip=IPADDRESS
IP address that should be offered by at least one DHCP server
-t, --timeout=INTEGER
Seconds to wait for DHCPOFFER before timeout occurs
-i, --interface=STRING
Interface to to use for listening (i.e. eth0)
-m, --mac=STRING
MAC address to use in the DHCP request
-u, --unicast
Unicast testing: mimic a DHCP relay, requires -s

Send email to [email protected] if you have questions regarding use
of this software. To submit patches or suggest improvements, send email to
[email protected]

It seems to me that this is a misconfiguration issue.

And one more thing want to know you that dhcp server port number is “49153(TCP)” instead of default ports is 67&68.

I am not even sure how this is going to work. In a "default" setup, UDP port number 67 is the destination port of a server, and UDP port number 68 is used by the client. You are showing only one port (“49153(TCP)”)...

In any case, troubleshooting a DHCP server with "non-default ports" is out of scope of nagios support.

[dca_admin]

Hello scott,

Thanks for your reply.

Yes i am the one who follow up with this issue in general support.

Now directly i am going to take the support in customer support.

Today i tried to modify some values in nagios xi like "-v -u -i ens192" and getting output is attached screenshot. Please check and let me know what exactly i received output after done some modification.

And today customer required need to monitor DHCP Server scopes in nagios xi. If suppose one scope reached end IP Addresses need to get alert in nagios. We identified one nagios plugin like "check_dhcp_scopes_all" i don't understand how to work with this plugin because it is powershell script. please help me to solve the issues and process to work. please check attached file of plugin.

[scottwilkerson]

I don't know of any DHCP plugins that can check custom ports