nrpe: CHECK_NRPE: Receive header underflow

[fsodah]

Why I recive above trying to monitor older ubuntu server ... when i run the comman from the nagios server it works ... via nagios GUI i get above message

Code: Select all

[root@nagios libexec]# /usr/local/nagios/libexec/check_procs 10.26.x.xx -w 5 -c 10 -s Z
PROCS OK: 0 processes with STATE = Z | procs=0;5;10;0;
[root@nagios libexec]# /usr/local/nagios/libexec/check_users 10.26.x.xx -w 5 -c 10
USERS CRITICAL - 1 users currently logged in |users=1;10.26.x.xx;-w;0
[root@nagios libexec]# /usr/local/nagios/libexec/check_nrpe -H 10.26.x.xx
NRPE v2.15
[root@nagios libexec]# /usr/local/nagios/libexec/check_nrpe -H localhost
NRPE v3.2.1
[root@nagios libexec]# 

Actually I dont have the permission to change anything on the client ... i have only the permission to sniff the nrpe check process ... so i cant reinstall or update any packages

[benjaminsmith]

Hello @fsodah,

I noticed that you are running the commands as root from the command line. Try testing this again but login as nagios, su - nagios and post any error messages to thread.

Also, the remote host is running version 2 while the Nagios server has version 3 installed, and there was a security change in version 3..

Try adding a -2 to your check command to force v2 packets.

Code: Select all

usr/local/nagios/libexec/check_nrpe -2 -H 10.26.x.xxx -c <check>

[fsodah]

I will check it tomorrow ..and update you

[benjaminsmith]

Hello @fsodah,

I will check it tomorrow ..and update you

Sounds good.

[fsodah]

One thing how can I add option -2 in the nagios gui ... or this just an check point to see the error of different version between nrpe

[benjaminsmith]

Hello,

You can do this by modifying the check command for check_nrpe. Go to Admin > CCM > Commands search for check_nrpe and then modify the command string.

check_nrpe.png

[fsodah]

I will create new one since I already use nrpe feature for huge number of linux updated servers ..am I right or far away off

[lmiltchev]

You are correct. If you modify your "original" check_nrpe command, this will affect ALL services that use it!

So, if you would like to use the "-2" flag on a limited number of services, you would need to create a new (custom) command. You can easily clone the original one, then add the "-2" to it. Then, you will need to modify your services to use your "custom" command instead of the original one. This is easily done under the "Service Management" ("Common Settings" tab), by selecting your new command from the "Check command" drop-down menu, clicking on "Save", and applying configuration.

Let us know if this helped.

[fsodah]

Noted ... I ll try it and get back

[lmiltchev]

Sure, we will keep the thread open.