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Re: custom Nagios check script not returning value to Nagios

Posted: Wed Jun 05, 2013 3:55 pm
by theace18
when I try putting "sudo" in front of the command in the nrpe.cfg file, NRPE replies back on Nagios with an "Unable to Read Output".

I have also ensured that the execute bit on the MegaCli64 file is set.

[root@nas1 bin]# ls -al|grep MegaCli
-rwxr-xr-x 1 root root 2236264 Jun 11 2012 MegaCli64

Any other suggestions before I claim this as an impossible task?

Re: custom Nagios check script not returning value to Nagios

Posted: Wed Jun 05, 2013 4:25 pm
by abrist
You will need to add the script to the sudoers file.
To set the suid execute bit:

Code: Select all

chmod u+s <script>
chmod u+s <bin>

Re: custom Nagios check script not returning value to Nagios

Posted: Wed Jun 05, 2013 4:40 pm
by theace18
Done...Still not working.

[root@nas1 nrpe_raid_monitor]# ls -al
total 64
drwxr-xr-x 2 root root 58 Jun 5 14:32 .
drwxr-xr-x 5 root root 80 May 30 14:21 ..
-rw-r--r-- 1 root root 60919 Jun 5 13:47 MegaSAS.log
-rwsr-xr-x 1 root root 562 Jun 5 14:32 raid_monitoring_megaraid.sh

[root@nas1 nrpe_raid_monitor]# ls -al /usr/local/bin/MegaCli64
-rwsr-xr-x 1 root root 2236264 Jun 11 2012 /usr/local/bin/MegaCli64


I even set the nagios user to run ALL commands as sudo:

User nagios may run the following commands on this host:
(ALL) NOPASSWD: ALL

Run the script on the nas1 server using the nagios user (which gives out the correct output):

sh-3.2$ sudo ./raid_monitoring_megaraid.sh
CRITICAL: RAID Errors Present


Run the NRPE check manually on the Nagios server (which gives the WRONG output):

[root@nagios libexec]# ./check_nrpe -H nas1 -c check_raid_status
OK: No Errors Found

Re: custom Nagios check script not returning value to Nagios

Posted: Thu Jun 06, 2013 11:24 am
by abrist
Could you post a copy of your remote host's nrpe.cfg?

Re: custom Nagios check script not returning value to Nagios

Posted: Fri Jun 07, 2013 12:07 pm
by theace18
Here you go:

Code: Select all

#############################################################################
# Sample NRPE Config File
# Written by: Ethan Galstad ([email protected])
#
# Last Modified: 11-23-2007
#
# NOTES:
# This is a sample configuration file for the NRPE daemon.  It needs to be
# located on the remote host that is running the NRPE daemon, not the host
# from which the check_nrpe client is being executed.
#############################################################################


# LOG FACILITY
# The syslog facility that should be used for logging purposes.

log_facility=daemon



# PID FILE
# The name of the file in which the NRPE daemon should write it's process ID
# number.  The file is only written if the NRPE daemon is started by the root
# user and is running in standalone mode.

pid_file=/var/run/nrpe.pid



# PORT NUMBER
# Port number we should wait for connections on.
# NOTE: This must be a non-priviledged port (i.e. > 1024).
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

server_port=5666



# SERVER ADDRESS
# Address that nrpe should bind to in case there are more than one interface
# and you do not want nrpe to bind on all interfaces.
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

server_address=10.150.1.221



# NRPE USER
# This determines the effective user that the NRPE daemon should run as.
# You can either supply a username or a UID.
#
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

nrpe_user=nagios



# NRPE GROUP
# This determines the effective group that the NRPE daemon should run as.
# You can either supply a group name or a GID.
#
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

nrpe_group=nagios



# ALLOWED HOST ADDRESSES
# This is an optional comma-delimited list of IP address or hostnames
# that are allowed to talk to the NRPE daemon.
#
# Note: The daemon only does rudimentary checking of the client's IP
# address.  I would highly recommend adding entries in your /etc/hosts.allow
# file to allow only the specified host to connect to the port
# you are running this daemon on.
#
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

allowed_hosts=127.0.0.1,10.150.1.250,10.150.1.221



# COMMAND ARGUMENT PROCESSING
# This option determines whether or not the NRPE daemon will allow clients
# to specify arguments to commands that are executed.  This option only works
# if the daemon was configured with the --enable-command-args configure script
# option.
#
# *** ENABLING THIS OPTION IS A SECURITY RISK! ***
# Read the SECURITY file for information on some of the security implications
# of enabling this variable.
#
# Values: 0=do not allow arguments, 1=allow command arguments

dont_blame_nrpe=0



# COMMAND PREFIX
# This option allows you to prefix all commands with a user-defined string.
# A space is automatically added between the specified prefix string and the
# command line from the command definition.
#
# *** THIS EXAMPLE MAY POSE A POTENTIAL SECURITY RISK, SO USE WITH CAUTION! ***
# Usage scenario:
# Execute restricted commmands using sudo.  For this to work, you need to add
# the nagios user to your /etc/sudoers.  An example entry for alllowing
# execution of the plugins from might be:
#
# nagios          ALL=(ALL) NOPASSWD: /usr/lib/nagios/plugins/
#
# This lets the nagios user run all commands in that directory (and only them)
# without asking for a password.  If you do this, make sure you don't give
# random users write access to that directory or its contents!

# command_prefix=/usr/bin/sudo



# DEBUGGING OPTION
# This option determines whether or not debugging messages are logged to the
# syslog facility.
# Values: 0=debugging off, 1=debugging on

debug=0



# COMMAND TIMEOUT
# This specifies the maximum number of seconds that the NRPE daemon will
# allow plugins to finish executing before killing them off.

command_timeout=60



# CONNECTION TIMEOUT
# This specifies the maximum number of seconds that the NRPE daemon will
# wait for a connection to be established before exiting. This is sometimes
# seen where a network problem stops the SSL being established even though
# all network sessions are connected. This causes the nrpe daemons to
# accumulate, eating system resources. Do not set this too low.

connection_timeout=300



# WEEK RANDOM SEED OPTION
# This directive allows you to use SSL even if your system does not have
# a /dev/random or /dev/urandom (on purpose or because the necessary patches
# were not applied). The random number generator will be seeded from a file
# which is either a file pointed to by the environment valiable $RANDFILE
# or $HOME/.rnd. If neither exists, the pseudo random number generator will
# be initialized and a warning will be issued.
# Values: 0=only seed from /dev/[u]random, 1=also seed from weak randomness

#allow_weak_random_seed=1



# INCLUDE CONFIG FILE
# This directive allows you to include definitions from an external config file.

#include=<somefile.cfg>



# INCLUDE CONFIG DIRECTORY
# This directive allows you to include definitions from config files (with a
# .cfg extension) in one or more directories (with recursion).

#include_dir=<somedirectory>
#include_dir=<someotherdirectory>



# COMMAND DEFINITIONS
# Command definitions that this daemon will run.  Definitions
# are in the following format:
#
# command[<command_name>]=<command_line>
#
# When the daemon receives a request to return the results of <command_name>
# it will execute the command specified by the <command_line> argument.
#
# Unlike Nagios, the command line cannot contain macros - it must be
# typed exactly as it should be executed.
#
# Note: Any plugins that are used in the command lines must reside
# on the machine that this daemon is running on!  The examples below
# assume that you have plugins installed in a /usr/local/nagios/libexec
# directory.  Also note that you will have to modify the definitions below
# to match the argument format the plugins expect.  Remember, these are
# examples only!


# The following examples use hardcoded command arguments...

command[check_users]=/usr/lib64/nagios/plugins/check_users -w 5 -c 10
command[check_load]=/usr/lib64/nagios/plugins/check_load -w 40,35,30 -c 50,45,35
command[check_zombie_procs]=/usr/lib64/nagios/plugins/check_procs -w 5 -c 10 -s Z
command[check_total_procs]=/usr/lib64/nagios/plugins/check_procs -w 550 -c 600
command[check_VolGroup_00_00]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/mapper/VolGroup00-LogVol00
command[check_VolGroup_00_01]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/mapper/VolGroup00-LogVol01
command[check_VolGroup_00_02]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/mapper/VolGroup00-LogVol02
command[check_VolGroup_00_03]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/mapper/VolGroup00-LogVol03
command[check_VolGroup_01_00]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/mapper/VolGroup01-LogVol00
command[check_VolGroup01_LogVolDATA]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/mapper/VolGroup01-LogVolDATA
command[check_VolGroupDATA_LogVolDATA]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/mapper/VolGroupDATA-LogVolDATA
command[check_sda1]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/sda1
command[check_sda2]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/sda2
command[check_sda3]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/sda3
command[check_sda4]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/sda4
command[check_sda5]=/usr/lib64/nagios/plugins/check_disk -w 20% -c 10% -p /dev/sda5
command[check_sdb1]=/usr/lib64/nagios/plugins/check_disk -w 10% -c 8% -p /dev/sdb1
command[check_java]=/usr/lib64/nagios/plugins/check_procs -w 1:2 -c 1:3 -C java
command[check_mysqld_safe]=/usr/lib64/nagios/plugins/check_procs -w 1:2 -c 1:3 -C mysqld_safe

# The following examples allow user-supplied arguments and can
# only be used if the NRPE daemon was compiled with support for
# command arguments *AND* the dont_blame_nrpe directive in this
# config file is set to '1'.  This poses a potential security risk, so
# make sure you read the SECURITY file before doing this.

#command[check_users]=/usr/local/nagios/libexec/check_users -w $ARG1$ -c $ARG2$
#command[check_load]=/usr/lib64/nagios/plugins/check_load -w 40,35,30 -c 50,45,35
#command[check_disk]=/usr/local/nagios/libexec/check_disk -w $ARG1$ -c $ARG2$ -p $ARG3$
#command[check_procs]=/usr/local/nagios/libexec/check_procs -w $ARG1$ -c $ARG2$ -s $ARG3$


# custom additions
command[check_swap]=/usr/lib64/nagios/plugins/check_swap -w 30% -c 10%
command[check_mem]=/usr/lib64/nagios/plugins/check_mem.pl -u -w 100 -c 101
command[check_mysql_monitor_agent]=/usr/lib64/nagios/plugins/check_procs -w 1:2 -c 1:3 -C mysql-monitor-a
command[check_mount_opt]=/usr/local/scripts/check_mountpoints.sh /opt
command[check_iostat]=/usr/lib64/nagios/plugins/check_iostat -d sdb -w 25000 -c 40000
command[check_raid_status]=/opt/systems_scripts/nrpe_raid_monitor/raid_monitoring_megaraid.sh


Re: custom Nagios check script not returning value to Nagios

Posted: Fri Jun 07, 2013 1:01 pm
by abrist
Well, I was hoping for a simple syntax error in the file, but it looks good. I would agree with one of your earlier posts that the issue seems to be that when run remotely, the raid cli utility is not actually running (this has to be a permissions/security issue). Are you logging pam/sudo attempts? If so, post a good tail of that log. I wonder if there is some other restriction?
Is selinux enabled?

Code: Select all

getenforce
Do you have any odd settings in sudoers like tty restrictions?

Re: custom Nagios check script not returning value to Nagios

Posted: Wed Jun 19, 2013 10:43 am
by theace18
WOW! That was it. My sudo settings by default said:

Defaults requiretty

So I commented it out, and now it freakin works. Hallelujah!

Thank you so much for your help!

Re: custom Nagios check script not returning value to Nagios

Posted: Wed Jun 19, 2013 12:21 pm
by abrist
Congrats! Whew, I guess one of those strings was worth reaching for. Have a great week!