Centos7升级内核至5.4

[root@localhost ~]# uname -r
3.10.0-1160.71.1.el7.x86_64

[root@localhost ~]# rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org

[root@localhost ~]# yum install https://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm
[root@localhost ~]# rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm

[root@localhost ~]# yum --disablerepo="*" --enablerepo="elrepo-kernel" list available

[root@localhost ~]# yum --enablerepo=elrepo-kernel install -y kernel-lt
# lt = long time 长期支持内核
# ml = mainline  稳定主线版本

[root@localhost ~]# yum remove kernel-tools-libs-3.10.0-1160.71.1.el7.x86_64 -y

[root@localhost ~]# yum --disablerepo=\* --enablerepo=elrepo-kernel install kernel-lt-tools.x86_64 -y

[root@localhost ~]# awk -F \' '$1=="menuentry " {print i++ " : " $2}' /etc/grub2.cfg
0 : CentOS Linux (3.10.0-1160.71.1.el7.x86_64) 7 (Core)
1 : CentOS Linux (5.4.212-1.el7.elrepo.x86_64) 7 (Core)
2 : CentOS Linux (0-rescue-360be7143c8548b780881ff416ec5603) 7 (Core)

[root@localhost ~]# grep "^menuentry" /boot/grub2/grub.cfg | cut -d "'" -f2
CentOS Linux (3.10.0-1160.71.1.el7.x86_64) 7 (Core)
CentOS Linux (5.4.212-1.el7.elrepo.x86_64) 7 (Core)
CentOS Linux (0-rescue-360be7143c8548b780881ff416ec5603) 7 (Core)

[root@localhost ~]# grub2-editenv list
saved_entry=CentOS Linux (3.10.0-1160.71.1.el7.x86_64) 7 (Core)

[root@localhost ~]# grub2-set-default 'CentOS Linux (5.4.212-1.el7.elrepo.x86_64) 7 (Core)'

[root@localhost ~]# grub2-editenv list
saved_entry=CentOS Linux (5.4.212-1.el7.elrepo.x86_64) 7 (Core)

[root@localhost ~]# grub2-set-default 1
# 1代表第一行，即上面内核版本为5.4那行
[root@localhost ~]# grub2-editenv list
saved_entry=1

[root@localhost ~]# reboot
[root@localhost ~]# uname -r
5.4.212-1.el7.elrepo.x86_64