NRPE Command not defined

[awilson]

I apologize for opening this. There is a similar post open and it is a common issue, but the other user hasn't replied in a week and I can't find anything in the others that I am doing differently to cause this.

The remote host is running AIX 7. NRPE is v2.12 and the Nagios host is 5.4.4 on RHEL 6.

[[email protected] ~]$ /usr/local/nagios/libexec/check_nrpe -H remotehost-t 30 -c check_aix_filesystem -n -a '85 90'
NRPE: Command 'check_aix_filesystem' not defined.

nrpe.cfg on the remote host contains: command[check_aix_filesystem]=/usr/local/nagios/libexec/check_aix_filesystem $ARG1$

Other checks using nrpe work on this remote host. The script is there and is executable by the nagios user. (nagios:staff)

bash-4.3$ ps -ef | grep nrpe
46718 7995750 14221722 0 17:37:07 pts/0 0:00 grep nrpe
nagios 15204800 1 0 May 10 - 0:14 /usr/local/nagios/bin/nrpe -c /usr/local/nagios/etc/nrpe.cfg -n -d

Any ideas? Thanks!

[tgriep]

Could you post the full /usr/local/nagios/etc/nrpe.cfg file here so we can check the settings?
Also, run these commands and post the output so we can see the permissions of the script and that it can run as the nagios user.

Code: Select all

ls -l /usr/local/nagios/libexec/check_aix_filesystem
su nagios
/usr/local/nagios/libexec/check_aix_filesystem 85 90

Thanks

[awilson]

nrpe.cfg

Code: Select all

bash-4.3$ cat nrpe.cfg
#############################################################################
# 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=127.0.0.1



# 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
allowed_hosts=10.10.83.90,10.10.83.97



# 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=1



# 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/local/nagios/libexec/check_users -w 5 -c 10
command[check_load]=/usr/local/nagios/libexec/check_load -w 15,10,5 -c 30,25,20
command[check_mem]=/usr/local/nagios/libexec/check_mem -f -w 10 -c 5
#command[check_disk]=/usr/local/nagios/libexec/check_disk -w $ARG1 -c $ARG2 -p $ARG3
#command[check_disk]=/usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /
#command[check_zombie_procs]=/usr/local/nagios/libexec/check_procs -w 5 -c 10 -s Z
command[check_swap]=/usr/local/nagios/libexec/check_swap $ARG1$
#command[check_total_procs]=/usr/local/nagios/libexec/check_procs -w 150 -c 200
command[check_filesystems]=/usr/local/nagios/libexec/check_filesystems $ARG1$ $ARG2$
command[check_entitlement]=/usr/local/nagios/libexec/check_lpar_cpu -p
command[check_cpu_stats]=/usr/local/nagios/libexec/check_cpu_stats $ARG1$


# 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/local/nagios/libexec/check_load -w $ARG1$ -c $ARG2$
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 $ARG3$
command[check_procs]=/usr/local/nagios/libexec/check_procs $ARG2$
command[check_fs_aix]=/usr/local/nagios/libexec/check_fs_aix $ARG2$
command[check_init_service]=/usr/local/nagios/libexec/check_init_service $ARG2$
command[check_nmon_cpu]=/usr/local/nagios/libexec/check_nmon $ARG2$
command[check_init_service]=/usr/local/nagios/libexec/check_init_service
command[check_nmon_cpu]=/usr/local/nagios/libexec/check_nmon $ARG2$
command[check_init_service1]=/usr/local/nagios/libexec/check_init_service1
command[check_process]=/usr/local/nagios/libexec/check_process $ARG2$
command[check_process_wcs]=/usr/local/nagios/libexec/check_process_wcs $ARG1$
command[check_two_process]=/usr/local/nagios/libexec/check_two_process $ARG1$
command[check_process_wcs]=/usr/local/nagios/libexec/check_process_wcs $ARG1$
command[check_init_db2process]=/usr/local/nagios/libexec/check_init_db2process $ARG1$
command[check_Db2_database_size.sh]=/usr/local/nagios/libexec/check_Db2_database_size.sh $ARG1$
command[check_Db2_transaction_log_util.sh]=/usr/local/nagios/libexec/check_Db2_transaction_log_util.sh $ARG1$
command[check_Db2_backup.sh]=/usr/local/nagios/libexec/check_Db2_backup.sh $ARG1$
command[check_process_wcs1]=/usr/local/nagios/libexec/check_process_wcs1 $ARG1$
command[check_TSM_longrun2.sh]=/usr/local/nagios/libexec/check_TSM_longrun2.sh $ARG1$
command[check_TSM_longrun.sh]=/usr/local/nagios/libexec/check_TSM_longrun.sh $ARG1$
command[check_disk]=/usr/local/nagios/libexec/check_disk $ARG1$
command[check_disk_IO]=/usr/local/nagios/libexec/check_disk_io $ARG1$
command[check_mem1]=/usr/local/nagios/libexec/check_mem1 $ARG1$
command[check_process_wcs1]=/usr/local/nagios/libexec/check_process_wcs1 $ARG1$
command[check_process_wcs]=/usr/local/nagios/libexec/check_process_wcs $ARG1$
command[check_two_process]=/usr/local/nagios/libexec/check_two_process $ARG1$
command[check_mounts]=/usr/local/nagios/libexec/check_mounts.sh
command[check_string]=/usr/local/nagios/libexec/check_string
command[check_disk_inodes]=/usr/local/nagios/libexec/check_disk_inodes.sh $ARG1$

command[check_aix_paging]=/usr/local/nagios/libexec/check_aix_paging $ARG1$
command[check_aix_filesystem]=/usr/local/nagios/libexec/check_aix_filesystem $ARG1$
bash-4.3$

bash-4.3$ ls -l /usr/local/nagios/libexec/check_aix_filesystem
-rwxr-xr-x 1 nagios staff 2517 May 10 15:42 /usr/local/nagios/libexec/check_aix_filesystem
bash-4.3$

$ bash
bash-4.3$ /usr/local/nagios/libexec/check_aix_filesystem 85 90
OK: Filesystem space inside acceptable levels
bash-4.3$

I didn't use su nagios ... because we log in with ssl certs instead of passwords.
Thanks

[tgriep]

The nrpe.cfg looks like it is configured OK and that the command runs in a shell and that is good as well.

When you created the command in the nrpe.cfg file, did you restart the nrpe agent?
That is needed as at startup, it loads the config file with any new changes so try doing that now to see if that fixes the issue.

[awilson]

Restarting the remote nrpe agent seems to have resolved it. Is this correct for future reference?

• 1. Install the script in the ../libexec directory with proper permissions
  2. Add the command entry to nrpe.cfg
  3. Restart the remote nrpe agent

Also, it is not necessary to add the new remote script as a "command" on the Nagios XI host because the check_nrpe command is what concerns Nagios XI at this point and that is what is being used from the Nagios XI host. The remote script name given to the check_nrpe check is simply a literal that is handed off to the remote nrpe agent. Is this a correct understanding?

Thanks!

[lmiltchev]

This is correct. The commands are defined in the nrpe.cfg file on the remote server. In order for the changes to take place, the NRPE agent needs to be restarted. Then, you can call any of the defined commands (on the remote machine) by running the check_nrpe plugin from the command line on the Nagios XI server:

Code: Select all

/usr/local/nagios/libexec/check_nrpe -H <client ip> -c <command>

or

Code: Select all

/usr/local/nagios/libexec/check_nrpe -H <client ip> -c <command> -a <arguments>

[awilson]

Thank you. I apologize for needing remedial support //smile

We can close this.

Thanks!