First time I've been DDoS'ed... Help?

Non Cybersecurity expert here. 

I'm battling an ongoing intermittent internet outage that we determined is a prolonged DDoS attack targeting us.  ISP cyber security has determined this is a limited distribution DNS-based DDoS Attack from a "script kiddie" using the commonly available "PYFlooder" script.   It requests DNS entries for 100  million random URLs and spoofs the sender's address so that we receive the replies we didn't ask for.

We've failed over to our backup. As we change IP addresses, the …

cybersecurity ddos ed