CentOS8：删除多余内核
1. check up using kernel :
[root@test ~]# uname -a
Linux test 4.18.0-147.8.1.el8_1.x86_64 #1 SMP Thu Apr 9 13:49:54 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
2. check up kernel:
[root@test ~]# rpm -qa | grep kernel
kernel-modules-4.18.0-147.el8.x86_64
kernel-devel-4.18.0-147.8.1.el8_1.x86_64
kernel-devel-4.18.0-147.el8.x86_64
kernel-modules-4.18.0-147.8.1.el8_1.x86_64
kernel-headers-4.18.0-147.8.1.el8_1.x86_64
kernel-tools-4.18.0-147.8.1.el8_1.x86_64
kernel-tools-libs-4.18.0-147.8.1.el8_1.x86_64
kernel-4.18.0-147.el8.x86_64
kernel-core-4.18.0-147.el8.x86_64
kernel-4.18.0-147.8.1.el8_1.x86_64
kernel-core-4.18.0-147.8.1.el8_1.x86_64
3. remove kernel:
[root@test ~]# dnf remove kernel-core-4.18.0-147.el8.x86_64
4. reboot :
[root@test ~]# reboot