Hard limit on data usage?
I'm considering using Digital Ocean but am reluctant to sign up while there's still any possibility that I can get hit with a 3 to 6 digit bill out of the blue because someone is DOSing my droplet or something else goes haywire that causes traffic to significantly exceed my plan's transfer cap. (It tentatively looks like a bill much higher than $15,000,000 is theoretically impossible at the $5/month service tier, assuming 40 Gb/sec full duplex for the entire month...presumably something would catch on fire or someone would pull the plug before then, but even at 40 Mb/sec nonstop one-way that's still around a $7500 bill.)
In short, I'm hoping someone from Digital Ocean can notify me when they've added a transfer capacity tripwire to their management system that is guaranteed to automatically shut down a droplet when (according to Digital Ocean's own metering) it exceeds its monthly transfer quota.
A vnstat solution, etc., running periodically in the droplet isn't a solution: it isn't foolproof and it can't read traffic from Digital Ocean's perspective. An email alert doesn't solve the problem either because email is neither reliable nor instantaneous, charges still accrue after the mail is sent, and I may not be available or able to check email, let alone shut down the droplet in a timely manner.
In normal circumstances I expect to use less than 1 GB/day.
As soon as this transfer limit short circuit feature exists I'll sign up.