external scripts and exit codes

[moses.moore]

I'm writing a new external script. It works pretty well, and I can test it with `zabbix_agentd -t 'app_thing[param1]`. I'm glad it can do freeform text and not depend on restrictive formats.

I insist on stuff that I write to fail gracefully, so I'm testing with bad data, and expecting that the Zabbix agent will recognize that something failed. In the external script I use error messages and "exit 1" where 1 is something not 0, as is normal in writing shell scripts.

Here's a dummy external script

#!/bin/sh
[ "$1" == 'ping' ] && echo 1 && exit 0
echo "ERR_invalid_param" && exit 1

So when I try testing with valid data:

$ zabbix_agentd -t 'app_thing[ping]'
app_thing[ping]          [t|1]

So far so good. Now trying with something that should throw an error:

$ zabbix_agentd -t 'app_thing[xyzzy]'
app_thing[xyzzy]         [t|ERR_invalid_param]

I'm confused because I expected that 't' (true) to be a 'f' (false) because the external script returned a non-zero exit code.

When writing a Zabbix external script, how should I signal to the zabbix agent that the external script failed? Maybe I need to write to stderr instead, leaving stdout empty? Does the zabbix agent always return 't' to the server even if the external script fails?

[Atsushi]

exit code is not handling.

By using a script such as the following, what do not you create a trigger to be considered an error if the value is 0?

#!/bin/sh
[ "$1" == 'ping' ] && echo 1 && exit 0
echo 0

That 't' is not 'true'.
't' is data type for 'text'.
Please try get values for other keys.

ex.
'u' : Unsigned int 64
'd' : Double
's' : String

[moses.moore]

What is the difference between 's' string and 't' text?

Could you remind to me where in the Zabbix documentation is described " 't' is data type for text" ?

I found https://www.zabbix.com/documentation...types/external
but this page does not describe 't'.

[Atsushi]

zabbix_agentd's '-t' option is just for testing.
You do not need to be checked that charactor before '|'.
If you want more details, please check the zabbix_agentd program source.

src/libs/zbxsysinfo/sysinfo.c : function test_parameter()

That difference with 's' and 't' is short string or large text data.
I think that difference like a data type with VARCHAR(255) and TEXT on DBMS.