Nagios Support Forum

I am periodically getting (No output on stdout) stderr on my NCPA windows clients in passive mode. The Linux Nagios server logs (/usr/local/nagios/var/nagios.log) look like the following:
1753202794] PASSIVE HOST CHECK: WinSrv01;0;OK: Agent_version was 3.1.3
[1753202795] PASSIVE SERVICE CHECK: WinSrv01;CPU Usage;0;(No output on stdout) stderr: << Error
[1753202795] PASSIVE SERVICE CHECK: WinSrv01;OS Disk Usage;0;(No output on stdout) stderr: << Error
[1753202795] PASSIVE SERVICE CHECK: WinSrv01;Memory Usage;0;OK: Memory usage was 53.00 % (Available: 4.23 GiB, Total: 9.00 GiB, Free: 4.23 GiB, Used: 4.77 GiB)
[1753203034] PASSIVE HOST CHECK: WinSrv02;0;PING OK - Packet loss = 0%, RTA = 0.29 ms
[1753203034] PASSIVE SERVICE CHECK: WinSrv02;CPU Usage;0;(No output on stdout) stderr: << Error
[1753203034] PASSIVE SERVICE CHECK: WinSrv02;OS Disk Usage;0;OK: Used_percent was 35.60 %
[1753203034] PASSIVE SERVICE CHECK: WinSrv02;Memory Usage;0;OK: Memory usage was 31.70 % (Available: 5.47 GiB, Total: 8.00 GiB, Free: 5.47 GiB, Used: 2.53 GiB)
[1753203044] PASSIVE HOST CHECK: WinSrv01;0;OK: Agent_version was 3.1.3
[1753203044] PASSIVE SERVICE CHECK: WinSrv01;CPU Usage;0;OK: Percent was 0.00 %
[1753203044] PASSIVE SERVICE CHECK: WinSrv01;OS Disk Usage;0;OK: Used_percent was 39.70 %
[1753203044] PASSIVE SERVICE CHECK: WinSrv01;Memory Usage;0;(No output on stdout) stderr: << Error

There does not seem to be any set pattern to the failures. Any check can go from providing the correct amount to sending an error and then go back to working again. Any idea for checking this? My sleep timer is set to 240 seconds on the Windows clients, not sure if that matters. Below are my checks:

[passive checks]
# Host check - This is to stop "pending check" status in Nagios
%HOSTNAME%|__HOST__ = system/agent_version
# Service checks
%HOSTNAME%|CPU Usage = cpu/percent --warning 80 --critical 90 --aggregate avg
%HOSTNAME%|OS Disk Usage = disk/logical/C:|/used_percent --warning 80 --critical 90 --units Gi
#%HOSTNAME%|Swap Usage = memory/swap --warning 60 --critical 80 --units Gi
%HOSTNAME%|Memory Usage = memory/virtual --warning 80 --critical 90 --units Gi
#%HOSTNAME%|Process Count = processes --warning 300 --critical 400

Hello @ereinhold,

Have you enable the debug log level? This will often give crucial information for resolving issues and it will be hard to diagnose what's happening without that enabled.