Strange not supported by zabbix agent behaviour.

[sspaise]

Hi All,

Please forgive me if this has come up before but I am currently slamming my head on the desk with a problem on some of our agents.

On our customer servers we run a command "system.run[invade agents]" which provides us with the current amount of connected users.

This item is working great for 150+ agents and reports the correct data, however on 20 or so agents the item keeps returning the dreaded "Not supported by Zabbix agent" error and disables the item.

These hosts are setup no differently to the 150+ working ones, and I can run the command manually using "zabbix_get" which returns the correct data, however when enabled at the front end, within a few minutes it errors and disables itself again.

After checking the zabbix logs for these hosts I am seeing the following error:

Can't parse list of active checks. Can't open JSON object ""

This appears just after I enable the item, then stops printing out to the log file once the item has disabled itself again.

We are not using active checks, just standard zabbix check and as previously mentioned this works fine on 150+ hosts already.

OS Version: CentOS 5.8 x86_64
Zabbix Server Version: 2.0.3
Zabbix Agent Version: 2.0.6

If you would like further information please let me know.

Is anyone here able to suggest any reason as to why these certain hosts are unable to run this automatically as I am fresh out of ideas?

Regards,
sspaise

[sspaise]

Ok so after some further investigation I have discovered some more info related to this.

I set the debug on the zabbix_agent and used zabbix_get to attempt to call the script using:

[root@FRTNS-LY-HA1 etc]# zabbix_get -s 127.0.0.1 -p 20093 -k system.run["invade agentcalls"]
ZBX_NOTSUPPORTED

After looking in the logs I could see that some of the environment variables were not being called correctly, so I corrected this and zabbix_get returned the information expected.

[root@FRTNS-LY-HA1 ~]# zabbix_get -s 127.0.0.1 -p 20093 -k system.run["invade agentcalls"]
0

Thinking this was then fixed I went on to the web frontend and enabled the items on these hosts, however after a few minutes these all returned to "Not Supported" and there is no further information in the debug logs as to why.

Can anyone tell me why this is possible using zabbix_get locally, but when enabled in front end it returns Not Supported again?

Regards,