Increase Plugin Output Length Restriction

This support forum board is for support questions relating to Nagios XI, our flagship commercial network monitoring solution.
Brick
Posts: 26
Joined: Thu Aug 29, 2013 6:02 am

Increase Plugin Output Length Restriction

Post by Brick »

I am using the Centos 64-bit VMware version.

I would like to increase the plugin output length, according to the core instructions I need to-
Nagios will only read the first 4 KB of data that a plugin returns. This is done in order to prevent runaway plugins from dumping megs or gigs of data back to Nagios. This 4 KB output limit is fairly easy to change if you need. Simply edit the value of the MAX_PLUGIN_OUTPUT_LENGTH definition in the include/nagios.h.in file of the source code distribution and recompile Nagios. There's nothing else you need to change!
However I am using the VM version so that file does not exist... is there another way of doing this?
jolson
Attack Rabbit
Posts: 2560
Joined: Thu Feb 12, 2015 12:40 pm

Re: Increase Plugin Output Length Restriction

Post by jolson »

There should be no problem performing a recompile of Nagios Core on an XI box. First, let's check what version of Nagios Core you're using:

Code: Select all

/usr/local/nagios/bin/nagios -V
In my case, the output told me I was using 4.0.8, so my procedure below is tuned for that particular version. Use the following to recompile Nagios Core with a higher plugin output limit (default on 4.0.8 is 8k, not 4k):

Code: Select all

cd /tmp
wget http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-4.0.8.tar.gz
tar zxf nagios-4.0.8.tar.gz
cd nagios-4.0.8
vi include/nagios.h
./configure
make all
make install
service nagios restart
When you vi into nagios.h, change the MAX_PLUGIN_OUTPUT_LENGTH value appropriately.

After these changes, you should be good to go!
Twits Blog
Show me a man who lives alone and has a perpetually clean kitchen, and 8 times out of 9 I'll show you a man with detestable spiritual qualities.
Brick
Posts: 26
Joined: Thu Aug 29, 2013 6:02 am

Re: Increase Plugin Output Length Restriction

Post by Brick »

Hi,

I removed the hash and changed the line to read-

Code: Select all

define MAX_PLUGIN_OUTPUT_LENGTH                16384
But I am getting the following error when I try to 'make all'-

Code: Select all

[root@rvdvnag01 nagios-4.0.8]# make all
cd ./base && make
make[1]: Entering directory `/tmp/nagios-4.0.8/base'
gcc -Wall -I.. -g -O2 -DHAVE_CONFIG_H -DNSCORE -c -o nagios.o nagios.c
In file included from ../include/downtime.h:30,
                 from nagios.c:39:
../include/nagios.h:271: error: expected â=â, â,â, â;â, âasmâ or â__attribute__â before âMAX_PLUGIN_OUTPUT_LENGTHâ
make[1]: *** [nagios.o] Error 1
make[1]: Leaving directory `/tmp/nagios-4.0.8/base'
make: *** [all] Error 2
[root@rvdvnag01 nagios-4.0.8]#
User avatar
tgriep
Madmin
Posts: 9190
Joined: Thu Oct 30, 2014 9:02 am

Re: Increase Plugin Output Length Restriction

Post by tgriep »

You need to put back the # symbol on that line and recompile. It is not there for commenting out the line, the compiler needs it for the define statement.
Be sure to check out our Knowledgebase for helpful articles and solutions!
Brick
Posts: 26
Joined: Thu Aug 29, 2013 6:02 am

Re: Increase Plugin Output Length Restriction

Post by Brick »

I thought that and tried it with the hashtag still in but it didn't make any difference- this is the output I am getting-

Code: Select all

ESX3 OK - storages : bcdpesx01-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-te
And this is what it should look like-

Code: Select all

ESX3 OK - storages : bcdpesx01-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-test-01=590070.00 MB (38.42%), vv-vds-test-02=1227547.00 MB (79.93%), vv-vds-test-03=490265.00 MB (31.92%), bcdpesx02-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-test-01=590070.00 MB (38.42%), vv-vds-test-02=1227547.00 MB (79.93%), vv-vds-test-03=490265.00 MB (31.92%), bcdpesx03-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-test-01=590070.00 MB (38.42%), vv-vds-test-02=1227547.00 MB (79.93%), vv-vds-test-03=490265.00 MB (31.92%), bcdpesx04-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-test-01=590070.00 MB (38.42%), vv-vds-test-02=1227547.00 MB (79.93%), vv-vds-test-03=490265.00 MB (31.92%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-test-01=590070.00 MB (38.42%), vv-vds-test-02=1227547.00 MB (79.93%), vv-vds-test-03=490265.00 MB (31.92%), bcdpesx05-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-test-01=590070.00 MB (38.42%), vv-vds-test-02=1227547.00 MB (79.93%), vv-vds-test-03=490265.00 MB (31.92%), bcdpesx06-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-test-01=590070.00 MB (38.42%), vv-vds-test-02=1227547.00 MB (79.93%), vv-vds-test-03=490265.00 MB (31.92%), bcdpesx07-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-test-01=590070.00 MB (38.42%), vv-vds-test-02=1227547.00 MB (79.93%), vv-vds-test-03=490265.00 MB (31.92%), bcdpesx08-OS=1963.00 MB (76.68%) 
And yes I did restart the service, in fact i restarted the whole machine!
jolson
Attack Rabbit
Posts: 2560
Joined: Thu Feb 12, 2015 12:40 pm

Re: Increase Plugin Output Length Restriction

Post by jolson »

What plugin are you using? Some plugins employ their own artificial limits on message sizing. check_nrpe is notable for having this complication.
Twits Blog
Show me a man who lives alone and has a perpetually clean kitchen, and 8 times out of 9 I'll show you a man with detestable spiritual qualities.
Brick
Posts: 26
Joined: Thu Aug 29, 2013 6:02 am

Re: Increase Plugin Output Length Restriction

Post by Brick »

The above post shows the results of the exact same check- the top one is what I can see on the nagiosxi box itself, the bottom one is what I can see on a Thruk server linked to the nagiosxi server via livestatus...
jolson
Attack Rabbit
Posts: 2560
Joined: Thu Feb 12, 2015 12:40 pm

Re: Increase Plugin Output Length Restriction

Post by jolson »

What plugin are you using to get the following output?

Code: Select all

ESX3 OK - storages : bcdpesx01-OS=1963.00 MB (76.68%), vv-vds-vswp-01=181593.00 MB (44.36%), vv-vds-vswp-02=190877.00 MB (46.63%), vv-vds-prod-01=1317525.00 MB (46.79%), vv-vds-prod-02=865586.00 MB (30.74%), vv-vds-prod-03=951033.00 MB (33.78%), vv-vds-te
Did you get this output by following a wizard, or implementing your own plugin? I would like to know so that I can use the plugin on my end and reproduce your issue.
Twits Blog
Show me a man who lives alone and has a perpetually clean kitchen, and 8 times out of 9 I'll show you a man with detestable spiritual qualities.
Brick
Posts: 26
Joined: Thu Aug 29, 2013 6:02 am

Re: Increase Plugin Output Length Restriction

Post by Brick »

Its using this plug-in-

https://exchange.nagios.org/directory/P ... st/details

Although I'm not sure if its customised from the orginal...

Running it with -l vmfs command.

Its not the only plugin effected tho- it effects all of the plug ins the same way
Brick
Posts: 26
Joined: Thu Aug 29, 2013 6:02 am

Re: Increase Plugin Output Length Restriction

Post by Brick »

I wrote a new check, here is the source-

Code: Select all

#!/bin/bash

echo "TESTING this is a test 1. this is a test 2. this is a test 3. this is a test 4 this is a test 5. this is a test 6. this is a test 7. this is a test 8. this is a test 9. this is a test 10. this is a test 11. this is a test 12. this is a test 13. this is a test 14."
exit $STATE_OK
This is the output I get-

Code: Select all

TESTING this is a test 1. this is a test 2. this is a test 3. this is a test 4 this is a test 5. this is a test 6. this is a test 7. this is a test 8. this is a test 9. this is a test 10. this is a test 11. this is a test 12. this is a test 13. this is a 
Locked