Which of the following should be noted when upgrading the E9000 server compute node? (Multiple choice)
A . It is recommended to upgrade the BMC software system and then upgrade the BIOS
B . When upgrading the BIOS, it is recommended to power off the business system first
C . In the process of upgrading, do not power on the business system, restart and other operations
D . During the upgrade process, it is forbidden to plug in the calculation node
Answer: ABCD