DONT do production stuff on friday afternoon. This friday evening we had an issue on production and just wanted to do a quick fix. The fix resulted in a ddos attack that we accidentally started on our servers in an IoT project. We contacted all customers' devices and asked them for response at the same time. Funny thing is that the devices are programmed to retry if a request fails until it is successful. We ended up with 4 hours downtime on production, servers were running again at 11pm.