We are really sorry to everyone who had trouble getting onto the site for practice challenge 3. Many users reported receiving Error 504 time out messages from our cloud provider CloudFlare making it at best difficult to see the challenge and at worst preventing you from submitting a solution.
The web team have been working hard to determine the cause and have identified it as a (presumably inadvertent) denial of service attack, launched by a user who was submitting thousands of attempts per hour. We applaud their ingenuity, but while we do our best to scale the system we can’t scale it that far, and the rules expressly forbid it!
3. Rapid fire multiple submissions put an unreasonable load on the servers and make it difficult for others to submit. Anyone who makes an unreasonable number of submissions will be open to disqualification. In the first instance this will mean that anyone who submits more than 20 times in 10 minutes will be disqualified.
We will work with our hosting provider to try to prevent this from happening in the future and will be working with the school to help explain to the team why this was not a good idea.
The site is recovering now and we expect it to be back to normal functioning in the next couple of hours.
As we said earlier, we are really grateful to everyone who emailed or sent in a bug report to report the timeout messages they were getting.
