If you use the Preview/Beta Grid (ADITI) then you know that there were problems in ADITI this week. But, last week on Friday parts of the main grid went down. The operations people via April Linden have posted an article on what happened.
See: The Story Behind Last Week’s Unexpected Downtime – 2016-05-09 10:22 AM
As part of the problem the Grid Status page went down. This is a tuning issue. That site normally has very few users. But, when the grid goes down users flood in and swamp the site. That is a common problem for hosting systems and there are ways to scale up to handle the load and down once demand passes. So, a future outage from overloading is now less likely.
When the Grid Status site is down there is a fall back: Twitter. See: SLGridStatus. This service stayed up. It has 12k+ followers.
I have the SL Grid Status in my favorites. Now I have added a Twitter link.