my initial question is on old forum https://monitoring-portal.org/woltlab/index.php?thread/42633-host-is-not-visible-via-api/#post260174
I upgraded to r2.8.1-1, but see exactly the same problem again.
The host was added via API after upgrade, so this is not an old data.
The problem is intermittent: it reproduces only for some checks.
Was it fixed in 2.8 ? Is there a workaround? Maybe I need to clean cache?
I tried to drop /var/cache/icinga2/* but it did not help.