How did GitHub survive that massive DDoS attack? Planning and preparation, of course. After 10 minutes of intermittent outages, the GitHub servers activated their DDoS mitigation service. The mitigation service rerouted incoming traffic and scrubbed the malicious packets, and about 10 minutes later the attackers gave up.

In addition to paying for DDoS mitigation services from companies like Cloudflare and Akamai, you can employ your standard endpoint security measures. Patch your servers, keep your Memcached servers off the open internet, and train your users to recognize phishing attacks.