number of unreachable hosts in a group?

[whitehat]

Hi!
Let's imagine I have a 1000 hosts in a group, and I want to have a trigger that fires when more than 10 hosts are unreachable. Could not find a solution for this problem, any suggestions?

[Firm]

I suppose you should write some code to retrieve metric via event.get API function to send number of such hosts back to Zabbix as metric. And create trigger on this metric.