different result for zabbix_get and zabbix_agentd

[frankcheong]

I have created a userparameter to cable the no of open files for a particular user. It works perfectly when I directly issue the command in OS level as well as testing with zabbix_get -t. While it did provide different value (I also have no idea why this script produce this value). Here is the details:-

UserParameter=NoOfOpenFiles[*],/opt/zabbix/etc/noOfOpenFiles.sh "$1"

[root@server ~# /opt/zabbix/etc/noOfOpenFiles.sh apache
300
[root@server ~]# /opt/zabbix/sbin/zabbix_agentd -t NoOfOpenFiles[apache]
NoOfOpenFiles[apache]                    [t|295]
[root@server ~]# /opt/zabbix/bin/zabbix_get -s 127.0.0.1 -p 10050 -k NoOfOpenFiles[apache]
25

/opt/zabbix/etc/noOfOpenFiles.sh

#!/bin/bash

/usr/sbin/lsof -nu ${1} | /usr/bin/wc -l

This problem happens with zabbix_agent 1.8.9 as well as 1.8.12 running under rhel 5.3

It is really strange. Let me know if additional information is needed.

I suspect it is also a permission related problem. Coz I would obtain the value 25 (which is the result reported by zabbix_get) when run the lsof command under a non-privilege account.

[root@server ~] su - zabbix -c '/opt/zabbix/etc/noOfOpenFiles.sh apache'
25
[root@server ~] su zabbix
[zabbix@server ~] /usr/sbin/lsof -nu apache | /usr/bin/wc -l
25
[zabbix@server ~]$ sudo /usr/sbin/lsof -nu apache | /usr/bin/wc -l
303

So that means zabbix already have the rights to execute lsof thru sudo coz I have granted the user zabbix to run all commands thru sudoer below:-

User_Alias MONITOR = zabbix
Cmnd_Alias LSOF = /usr/sbin/lsof
Cmnd_Alias NOOFOPENFILES = /opt/zabbix/etc/noOfOpenFiles.sh

MONITOR ALL=NOPASSWD: ALL

While zabbix agent seems unable to successfully obtain the root privilege thus sudo. I know I can get around this problem thru allow root in zabbix_agentd.conf while I would like to know if there is better ways to get around with this problem.

[frankcheong]

Finally I know what is happening.

After upgrading to 1.8.12, the verbosity is much improved, I then located an error msg in the zabbix_agentd.log as below:-

sudo: sorry, you must have a tty to run sudo

After searching thru the internet. I found that in sudoer, there is a line:-

Defaults    requiretty

All I have to do is to remark this line

#Defaults    requiretty

And then everything works perfectly.