This has been happening on my Zabbix installation for as long as I can remember (across several versions, including 3.4.x,4.0,4.2, possibly even older as well). A picture would describe it best:

There is nowhere near 1000 items with missing data for over 10 minutes, yet the trigger is firing. Why? What steps can I take to troubleshoot this? I'd rather not disable the trigger entirely but it's starting to get more annoying.
There is nowhere near 1000 items with missing data for over 10 minutes, yet the trigger is firing. Why? What steps can I take to troubleshoot this? I'd rather not disable the trigger entirely but it's starting to get more annoying.