NSCA error: invliad packet received


Hi all,

I have previously used Nagios and NSClient++ NRPE module to execute active checks on a win xp machine and it worked great.

Now I need to do passive checks so i decided to try out the NSCA module.I setup everything and had NSCLient send the results b to Nagios. Here is the error syslog message (located in /var/log/message) i gotten

daemon.info<30>: localhost Handling the connection… Apr 1 17:30:27 nsca[27467]:

daemon.err<27>: localhost Received invalid packet type/version from client - possibly due to

client using wrong password or crypto algorithm? Apr 1 17:30:27 nsca[27467]:

daemon.err<27>: localhost End of connection… Apr 1 17:30:27 nsca[27467]:

I have setup NSCA using this brillant guide (nagios.sourceforge.net/download/ … _Setup.pdf)

I am using Win32 0.3.1 NSClient++

I ddint set password and encryption method ( decryption=encryption=0) for both sides.

I tested using the NSCA command “my_cpu_check” which is in nsc.ini by default

my nagios configurations:

define service{

use passive_service

host_name winxp

service_description my_cpu_check

check_command check_dummy!0


define host{

use windows-server ; Inherit default values from a template

host_name winxp ; The name we're giving to this host

alias win xp machine ; A longer name associated with the host

address ; IP address of the host

max_check_attempts 1

process_perf_data 0

notification_interval 0 ; Resend notifications

active_checks_enabled 0 ; enable the check commands


The service was always in pending state.

Have been trying for a day. Would greatly appreciate any help. Thanks.



I reinstaslled NSCA and

The libs:




But this time, I ddint enable the dynamic link when i use ./configure for libmcrypt-2.5.8

Now its working!

I also found out that the monitoring host and the windows machine must be sync to a ntp server (time have to be synchronized) for NSCA to work properly