The rescheduling of scheduled downtimes doesn't work sometimes


I submitted a bug about this on github in late August, ScheduleDowntime skips time periods · Issue #9858 · Icinga/icinga2 · GitHub, but I wanted to check with the community if someone else has the same issue and a possible workaround if so.

For us the issue is quite frustrating since our on-call is awaken a couple of times during the night when this situation occurs. Often everything works fine, for weeks and months, but every now and then the rescheduling of a Scheduled Downtime just fails. The details and a way to reproduce the issue is attached to the bug report.

My question to you is: Am I using scheduled downtimes according to best practices? Am I missing something or configured something wrong? I’m quite surprised there is so little attention to this issue so I’m suspecting the issue is with how I use the functionality.

We run Icinga2 2.14.0 with two master nodes. Icinga Web 2 2.11.4, Director 1.10.2, icingadb module 1.0.2, IcingaDB 1.1.1, IcingaDB Redis 7.0.5.

And example of applied Scheduled Downtime that sometimes fails:

apply ScheduledDowntime "sd-<servicename>" to Service {
    author = "<my name>"
    comment = "Service is shutdown between 23:50 and 06:30"
    fixed = true
    assign where == "<service-name>"
    ranges = {
        "friday"	= "00:00-06:30,23:50-24:00"
        "monday"	= "00:00-06:30,23:50-24:00"
        "saturday"	= "00:00-24:00"
        "sunday"	= "00:00-24:00"
        "thursday"	= "00:00-06:30,23:50-24:00"
        "tuesday"	= "00:00-06:30,23:50-24:00"
        "wednesday"	= "00:00-06:30,23:50-24:00"

As a quick fix or even fix, i would change the check interval of the services to something like MO-FR 6:31-23:49 just to make sure that the scheduler cant schedule cant even schedule the job.