Trigger recovery with empty result ? or expression? Sorry for the noob question

[andy.anthoine]

Hi guys,
Sorry i tried a few things but it seems like i m doing something wrong... what should i write in the RECOVERY EXPRESSION for my trigger to go back to ok, when there is NO VALUE returned by the SNMP CHECK
Bonus point : how to modify my expression to make it work with 6 AND 17 ?

https://imgur.com/a/LUcRj80

To be clear, i either recieve 6 or 17 meaning there is an error, or this retrieve NOTHING, blank, if it's ok

[ISiroshtan]

Hey man.

First thing needed to answer your question is to know how item data actually apears in Zabbix. Instead of trigger could you show screenshot of an item history when port is error disabled and when it's not?

Just shooting blindly with litle info you given you can try following:

If there is no data stored at all when port is not error disabled(item becomes unsuported with whatever error message), you can go with trigger expression like
nodata(5m)=0
No recovery expression needed.

This way when your switch/router/whatever_you_monitor returns any value from this OID - alert will fire. When there is no new value returned for 5 minutes - alert will be considered resolved and will auto close.