Link11 has released its DDoS report for Q1 2021 which revealed the number of DDoS attacks continued to grow. Almost every second DDoS attack (47%) targets hosting providers and ISPs. 69% of attacks were multi-vector attacks combining multiple techniques. DDoS attackers stick to their target even if they are unsuccessful: 1489 minutes was the longest attack (>24 h). Long recovery times, which can be twice or three times as long as the actual attack, would still have to be considered.
Source: https://www.helpnetsecurity.com/2021/05/03/ddos-attackers-stick-to-their-target/