This is similar to ZBXNEXT-684 but more extensive. Seems like it should be a separate request. Sorry if that is not cool.

1) When adding new IT Services, the SLA calculation uses the data collected starting 'right now' instead of going back and using all the collected historical data for the assigned trigger.
2) This is okay and understandable, but then all the SLA graphs and reports back-fill the data as being all 100%. There is no way to know when the cutoff is for real data vs filled in data.

Example: I just added an IT service and attached it to a trigger that has been active for two months. We have had some downtime the past week and the SLA always shows 100%. When I click the graph button, I see green bars going back to January 1.

If I click on the blue SLA bar and set the report to anything, it's always 100%. Say, weekly in 2009 before we ever ran Zabbix, it shows it had been up 100% of the time when it never actually existed.

Requested solution/fix:

1) [optional] Allow the SLA to be calculated using already stored data, not just starting on this date and going forward.
2) [mandatory] Do not display SLA data for data that does not exist, cut it off at whatever the start point of the calculated SLA is.

I realize that calculating the SLA up to parents with data sets that do not start at the same time is difficult. Perhaps those gaps should be filled in with 100% but it doesn't make sense to me that data is back filled all the way back to 2007.

Note that this is actually Zabbix 1.8.6 but I can't put that in the Affects Version/s field above.

Thanks!