a lot of people noticed that for a while earlier this afternoon we were just serving a message that said "Cannot GET /" instead of your home timeline. for Reasons, this wasn't an issue that affected everyone who tried to load their timeline during the outage period, but judging based on our usage statistics, it affected about 90% of people.
what we know for sure about the root cause is that for some reason, this error got unintentionally served to someone by a server that isn't normally supposed to serve the timeline page, then our cache provider cached it because it caches everything by default and -- it not being an error we ever intended to serve -- we didn't put a "no cache" header on it. flushing the cache for this path at our cache provider fixed the issue.
we're not 100% sure why we served this error in the first place, and we're putting off a further investigation until we're back at work on monday, but we suspect it's some sort of intermittent glitch in the server's configuration that we're going to try to fix or work around.
YOU CANNOT GET YE /
