CentOS6内核更换为：2.6.32-504.3.3.el6.x86_64

rpm -ivh http://www.johntitorblog.com/wp-content/oldfile/kernel-firmware-2.6.32-504.3.3.el6.noarch.rpm

rpm -ivh http://www.johntitorblog.com/wp-content/oldfile/kernel-2.6.32-504.3.3.el6.x86_64.rpm --force

---

CentOS7内核更换为：3.10.0-229.1.2.el7.x86_64

rpm -ivh http://www.johntitorblog.com/wp-content/oldfile/kernel-3.10.0-229.1.2.el7.x86_64.rpm --force

---

查看内核是否安装成功

rpm -qa | grep kernel

然后重启。

用uname -r 查看是否生效

---

此外，centos7切换内核更完整的文章如下。

1. 添加repo库

yum -y install https://www.elrepo.org/elrepo-release-7.el7.elrepo.noarch.rpm

2. 导入签名

rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org

3. 差看长期支持版本

[root@localhost ~]# yum --disablerepo="*" --enablerepo="elrepo-kernel" list available | grep kernel-lt
kernel-lt.x86_64                        5.4.210-1.el7.elrepo       elrepo-kernel
kernel-lt-devel.x86_64                  5.4.210-1.el7.elrepo       elrepo-kernel
kernel-lt-doc.noarch                    5.4.210-1.el7.elrepo       elrepo-kernel
kernel-lt-headers.x86_64                5.4.210-1.el7.elrepo       elrepo-kernel
kernel-lt-tools.x86_64                  5.4.210-1.el7.elrepo       elrepo-kernel
kernel-lt-tools-libs.x86_64             5.4.210-1.el7.elrepo       elrepo-kernel
kernel-lt-tools-libs-devel.x86_64       5.4.210-1.el7.elrepo       elrepo-kernel

4. 安装长期稳定版本

yum --enablerepo=elrepo-kernel install kernel-lt

5. 切换内核版本

# 查看所有可用内核版本
[root@localhost ~]# grubby --info=ALL | grep ^kernel
kernel=/boot/vmlinuz-0-rescue-e6b1be1665514df5b07c55fd799bfbf0
kernel=/boot/vmlinuz-5.4.210-1.el7.elrepo.x86_64
kernel=/boot/vmlinuz-3.10.0-1160.66.1.el7.x86_64
kernel=/boot/vmlinuz-3.10.0-1160.el7.x86_64
kernel=/boot/vmlinuz-0-rescue-f8f95d1d9b764ae99f2fc289a16fc263
#查看默认的内核版本
[root@localhost ~]# grubby --default-kernel
/boot/vmlinuz-3.10.0-1160.66.1.el7.x86_64
# 设置内核版本
grubby --set-default "/boot/vmlinuz-5.4.210-1.el7.elrepo.x86_64"
#重启
reboot

6. 删除旧内核

[root@localhost ~]# rpm -qa | grep kernel
kernel-tools-libs-3.10.0-1160.66.1.el7.x86_64
kernel-3.10.0-1160.66.1.el7.x86_64
kernel-tools-3.10.0-1160.66.1.el7.x86_64
kernel-3.10.0-1160.el7.x86_64
kernel-lt-5.4.210-1.el7.elrepo.x86_64

yum remove kernel-tools-libs-3.10.0-1160.66.1.el7.x86_64 \
kernel-3.10.0-1160.66.1.el7.x86_64 \
kernel-tools-3.10.0-1160.66.1.el7.x86_64 \
kernel-3.10.0-1160.el7.x86_64

[root@localhost ~]# uname -r
5.4.210-1.el7.elrepo.x86_64

7. 离线升级
7.1 下载rpm包

curl -O https://mirrors.aliyun.com/elrepo/kernel/el7/x86_64/RPMS/kernel-lt-5.4.212-1.el7.elrepo.x86_64.rpm
7.2 安装

yum install kernel-lt-5.4.212-1.el7.elrepo.x86_64.rpm
7.3 批量删除旧核心

rpm -qa | grep kernel | grep -v $(uname -r) | awk '{print "yum remove -y "$1}' | sh
END