CMK version: 2.2.0
OS version: Windows Server 2022 Standard
Error message: No errors, returning data, just not the right data.
See screenshot from the output of the service check.
When looking at the parameters of the check the manual says “This check uses the output of “netsh dhcp server show mibinfo” as sent by the Checkmk windows agent when using the appropriate agent plugin.”
So if I go to the host and run the command manually I get correct outputs.
Any idea how I troubleshoot this?
any advice from the community?
For troubleshooting the agent output section for the DHCP would be relevant.
Can you please post this section only?
Best way is to download the agent output from the webinterface.
Hi community,
I have the same problem.
Check_MK Agent: 2.2.0
Check_MK Server: 2.2.0p24
Windows Server: Server 2022 in German
I downloaded the agent output from the webinterface and the vlaues looks fine
<<<win_dhcp_pools>>>
MIB-Anzahl:
Entdeckungen = 261526.
Angebote = 243410.
Verzgerte Angebote = 0.
Anforderungen = 231945.
Acks = 242681.
Naks = 228.
Abweisungen = 4.
Freigaben = 46792.
ServerStartTime = Mittwoch, 17. April 2024 13:16:23
Bereiche = 58.
Bereiche mit konfigurierter Verzgerung= 0
Subnetz = 10.11.12.0.
Anzahl der verwendeten Adressen = 860.
Anzahl der freien Adressen = 422.
Anzahl der anstehenden Angebote = 0.
The only thing I notice is the umlaut in the german output. (“Verzögerte Angebote” und “Bereiche mit konfigurierter Verzögerung”).
The graphs represent 0,X values.
I tried to find out on the Check_MK server what Check_MK does with the values.
I looked under /omd/sites/SITENAME/ for sites containing “dhcp_stats”.
I found the following:
./var/nagios/archive/nagios-04-19-2024-00.log:[1713444478] INITIAL SERVICE STATE: dhcp1;DHCP Stats;OK;HARD;1;Discovers: {int(f)}/s, Offers: {int(f)}/s, Requests: {int(f)}/s, Acks: {int(f)}/s, Nacks: {int(f)}/s, Declines: {int(f)}/s, Releases: {int(f)}/s, Scopes: {int(f)}/s
und
./var/rrdcached/rrd.journal.1713874646.401784:update /opt/omd/sites/SITENAME/var/pnp4nagios/perfdata/dhcp1/DHCP_Stats_Discovers.rrd 1713877388:0.423661
./var/rrdcached/rrd.journal.1713874646.401784:update /opt/omd/sites/SITENAME/var/pnp4nagios/perfdata/dhcp1/DHCP_Stats_Offers.rrd 1713877388:0.390302
./var/rrdcached/rrd.journal.1713874646.401784:update /opt/omd/sites/SITENAME/var/pnp4nagios/perfdata/dhcp1/DHCP_Stats_Requests.rrd 1713877388:0.477036
./var/rrdcached/rrd.journal.1713874646.401784:update /opt/omd/sites/SITENAME/var/pnp4nagios/perfdata/dhcp1/DHCP_Stats_Acks.rrd 1713877388:0.483707
./var/rrdcached/rrd.journal.1713874646.401784:update /opt/omd/sites/SITENAME/var/pnp4nagios/perfdata/dhcp1/DHCP_Stats_Nacks.rrd 1713877388:0.003336
./var/rrdcached/rrd.journal.1713874646.401784:update /opt/omd/sites/SITENAME/var/pnp4nagios/perfdata/dhcp1/DHCP_Stats_Declines.rrd 1713877388:0
./var/rrdcached/rrd.journal.1713874646.401784:update /opt/omd/sites/SITENAME/var/pnp4nagios/perfdata/dhcp1/DHCP_Stats_Releases.rrd 1713877388:0.076726
./var/rrdcached/rrd.journal.1713874646.401784:update /opt/omd/sites/SITENAME/var/pnp4nagios/perfdata/dhcp1/DHCP_Stats_Scopes.rrd 1713877388:0
Maybe this will help.
Where can I actually find the piece of code that is responsible for processing this check plugin on the server?
Best regards
On the Check_MK server in /omd/sites/SITENAME/lib/python3/cmk/base/plugins/agent_based/win_dhcp_pools.py I found the following:
# Example outputs from agent:
#
# <<<win_dhcp_pools>>>
#
# MIB-Anzahl:
# Entdeckungen = 0.
# Angebote = 0.
# Anforderungen = 0.
# Acks = 0.
# Naks = 0.
# Abweisungen = 0.
# Freigaben = 0.
# ServerStartTime = Dienstag, 29. Juni 2010 19:08:55
# Bereiche = 1.
# Subnetz = 192.168.123.0.
# Anzahl der verwendeten Adressen = 0.
# Anzahl der freien Adressen = 239.
# Anzahl der anstehenden Angebote = 0.
#
# MIBCounts:
# Discovers = 0.
# Offers = 0.
# Requests = 0.
# Acks = 1.
# Naks = 0.
# Declines = 0.
# Releases = 0.
# ServerStartTime = Sunday, May 25, 2008 12:38:06 PM
# Scopes = 1.
# Subnet = 172.16.11.0.
# No. of Addresses in use = 1.
# No. of free Addresses = 23.
# No. of pending offers = 0.
In the expected example output, the two lines are missing:
Verzgerte Angebote = 0.
Bereiche mit konfigurierter Verzgerung= 0
Is it possible that this is why this plugin no longer works? The two additional lines in the output on a Windows server 2022? Unfortunately, I don’t have a Windows DHCP server < 2022 to check the output there.
Then you can find the following in the Python script:
# Attention:
#
# Tried to get the win-agent plugin to report always in utf-8, unfortunately without luck.
# ...that's the reason why french translations with special characters must get provided like here.
As a first step, I’ll try to get the CMD output in UTF-8. Let’s see how this is supposed to work?!
If that doesn’t help, I’ll try to filter out the two lines.
.
.
.
If the CheckMK server receives the agent output in UTF-8, the check still does not work. 
I added the following line to win_dhcp_pools.bat after the “@echo off” line:
chcp 65001>nul
Now the downloaded agentoutput looks good belong the umlaut.
<<<win_dhcp_pools>>>
MIB-Anzahl:
Entdeckungen = 266707.
Angebote = 248047.
Verzögerte Angebote = 0.
Anforderungen = 237775.
Acks = 248740.
Naks = 237.
Abweisungen = 4.
Freigaben = 48225.
ServerStartTime = Mittwoch, 17. April 2024 13:16:23
Bereiche = 58.
Bereiche mit konfigurierter Verzögerung= 0
Greetings to the developer… maybe this will help with the French translation. 
Windows DHCP on 2022 in german will need this too, if this Verzögerung values will be monitored in future.
Unfortunately, filtering out the two lines was unsuccessful.
To do this, I expanded the line with the netsh call at the end:
| find /V "Verzögerte Angebote" | find /V "Bereiche mit konfigurierter Verzögerung"
The agent output looks good:
MIB-Anzahl:
Entdeckungen = 267284.
Angebote = 248542.
Anforderungen = 238357.
Acks = 249342.
Naks = 237.
Abweisungen = 4.
Freigaben = 48417.
ServerStartTime = Mittwoch, 17. April 2024 13:16:23
Bereiche = 58.
But the check still shows garbage
Discovers: {int(f)}/s, Offers: {int(f)}/s, Requests: {int(f)}/s, Acks: {int(f)}/s, Nacks: {int(f)}/s, Declines: {int(f)}/s, Releases: {int(f)}/s, Scopes: {int(f)}/s
I suspect the error in the plugin on the server.
Maybe here? Because the plugin outputs the lambda expression.
def check_win_dhcp_pools_stats(section: Section) -> CheckResult:
this_time = time.time()
value_store = get_value_store()
for line in section:
if len(line) > 0:
key = _WIN_DHCP_POOLS_STATS_TRANSLATE.get(line[0], line[0])
if key in [
"Discovers",
"Offers",
"Requests",
"Acks",
"Nacks",
"Declines",
"Releases",
"Scopes",
]:
value = _safe_int(line[1])
yield from check_levels(
get_rate(value_store, key, this_time, value),
metric_name=key,
render_func=lambda f: "{int(f)}/s",
label=key,
)