Python custom nagios script with beautiful soup - getting "NRPE: Unable to read output"

Question

I am trying to create a custom python 2 nagios script in order to be able to monitor individual pacemaker resources. I managed to have it working when its reading the input from a file but I cannot manage to make it work when the input is being collected from the cli.

So like this it works:


from __future__ import print_function
from bs4 import BeautifulSoup
import os,sys

with open ("/tmp/crm_output.txt","r") as f:
#with os.popen ("/usr/sbin/crm_mon -r -X") as f:
    contents = f.read()
    soup = BeautifulSoup(contents, 'lxml')
    resource_status = soup.find("resource").attrs["role"]
    resource_name = soup.find("resource").attrs["id"]

if resource_status == "Started":
    print("The status of " +resource_name + " is " + resource_status)
    sys.exit(0)
elif resource_status == "Stopped" or resource_status == "Stopped (disabled)":
    print("The status of " +resource_name + " is " + resource_status)
    sys.exit(1)
elif resource_status == "Failed":
    print("The status of " +resource_name + " is " + resource_status)
    sys.exit(2)
else:
    print("The status of " +resource_name + " is " + "UNKNOWN")
    sys.exit(3)

but if I uncomment this line:

with os.popen ("/usr/sbin/crm_mon -r -X") as f:

to have it read the input from the cli,it gives me the NRPE:unable to read output

The interesting thing is that when I run the script locally in the target server its giving me the correct ouput all the time. Like this:

[root@lb-01 tmp]# /usr/lib64/nagios/plugins/check_pacemaker.py
The status of api-lb-ip is Started

I suspect there is something wrong with how I read the output from the command but not being able to figure it out. Any recommendations where to look for more details?

Rohlik · Accepted Answer · 2019-08-12T08:41:07.570

This can be problem with your remote user which execute your script on remote server.
Default behavior is that only root can run cluster commands.
You can add your command /usr/sbin/crm_mon -r -X to /etc/sudoers something like:

nrpe            ALL=(ALL)       NOPASSWD: /usr/sbin/crm_mon -r -X

Replace nrpe with your remote user. You also need edit your Python script and add sudo before your command:

with os.popen ("sudo /usr/sbin/crm_mon -r -X") as f:

Hope that it helps.

Python custom nagios script with beautiful soup - getting "NRPE: Unable to read output"

1 Answers1