Hello,

Similar to the 1.6 bug below, we are experiencing the same behaviour in 1.8.6:

https://support.zabbix.com/browse/ZBX-978?page=com.atlassian.jira.plugin.system.issuetabpanels%3Aall-tabpanel

Today we had 5 hosts go down for about 1 hour and one-by-one they were rebooted. After the 5 hosts were up Zabbix server collected data for all 5 without issue but the Unreachable triggers never recovered.

We are watching the following for our 'unreachable' trigger:

=2

I was able to fix this later by stopping the agent on the server for 5 minutes, and restarting as a post in the Zabbix forum suggested.

Cheers,

Tim Vaillancourt