Can an item be monitored only at certain circumstance?

[ykdhan]

I am using Zabbix 5. As long as I know, there are item dependencies and trigger dependencies.
Other than that, I am curious if I can set a condition for an item to be monitored only at that condition.

For example, if one firewall device gives 0 ping back, then I want to start monitoring (or sending pings) to a L2 device which is above that firewall device.
So, my L2 device will be monitored not all the time but only when I get a trigger.

Is such functionality available in Zabbix?

[Hernandes Martins]

No, not condition available in item, condition just on trigger.


Regards

[ykdhan]

Thank you for clarifying that.

[ripperSK]

you can code an API call to enable / disable an item in a script and have this script called after specific trigger.

Effort vs. result of this is questionable and secondly - there's no harm in collecting an item data that you just don't use.

If you ping an IP that's unreachable - it's just item values - no harm done...

[ykdhan]

I am worried about wasting cpu and memory of zabbix server.
I need to monitor about 7000 FW devices and also keep track of L2 devices as well because some problems could come from or dependent on L2s.
Then, I will have 14000 devices (items) to ping.

[ripperSK]

then I suggest you code an API call to enable /disable a certain host after a certain trigger is fired :

https://www.zabbix.com/documentation/4.0/manual/api/reference/host/update#enabling_a_host

alternatively you can distribute your zabbix server load by using zabbix proxies that will ping your equipment instead of the server.

I would only suggest that you look into monitoring via SNMP / SNMP traps - where a firewall can report if a port where L2 switch is connected went down or not.

[ykdhan]

Thank you so so much! Your advice is great. I will try using zabbix proxies and if there is too much load I will code an API call.

[ykdhan]

ripperSK

At this moment, I have a question related to the API call action.
I am not sure if this is true but I have heard that Zabbix does load configurations such as item ability (enabled, disabled) with 1 minute interval.
If this is true, even though I call an API call to enable or disable certain item, it won't apply to Zabbix server right away. There will be maximum 1 minute delay to execute the call.
Is there a way to reduce the interval or is there a way to force-load such configuration? Would this cause another cpu load?
Thank you!

[ripperSK]

I am unaware of such limitation or interval. If you feel like zabbix server is requesting an item that you disabled use runtime argument :

 zabbix_server -R config_cache_reload

this forces server to re-read all the configured items and also their enabled/disabled state. It is also available for zabbix proxy.

secondly I advise you to enable / disable whole host using the API as it's easier for debugging purposes and immediately visible in the web interface.

[ykdhan]

Awesome! This helps a lot. I will enable/disable the whole host instead of item. Thank you so much.