I have been involved in the secondary development of Hadoop for 2 years. The following article summarizes my experience in upgrading from Hadoop 2.7 to Hadoop 3.2 in-place at qihoo.360. https://zyun.360.cn/blog/?p=1458
Currently, I am eager to actively participate in the community and contribute to the development of YARN code, such as Global Scheduler and YARN Router. Best wishes!
