本文主要是和另一篇手动安装内核配对的https://www.anidays.com/2024/79.html，更新内核后就得内核基本没啥用了，我喜欢把他们卸载掉，节约点VPS存储空间，虽然是杯水车薪，但乐于折腾。
环境：CentOS 7 X64 2009，其他机器仅供参考。
1、首先通过uname -r命令获取当前使用内核版本，返回数据如下：
[root@wiki-hk-web ~]# uname -r
3.10.0-1160.92.1.el7.x86_64然后我们看下系统上一共有多少内核，执行：
rpm -qa | grep kernel返回如下
[root@wiki-hk-web ~]# rpm -qa | grep kernel
kernel-3.10.0-1160.92.1.el7.x86_64
kernel-tools-3.10.0-1160.95.1.el7.x86_64
kernel-devel-3.10.0-1160.95.1.el7.x86_64
kernel-3.10.0-1160.95.1.el7.x86_64
kernel-ml-5.15.60-1.el7.x86_64
kernel-ml-devel-5.15.60-1.el7.x86_64
kernel-devel-3.10.0-1160.83.1.el7.x86_64
kernel-devel-3.10.0-1160.92.1.el7.x86_64
kernel-tools-libs-3.10.0-1160.95.1.el7.x86_64
kernel-headers-3.10.0-1160.95.1.el7.x86_64
kernel-3.10.0-1160.45.1.el7.x86_64
kernel-devel-3.10.0-1160.88.1.el7.x86_64
kernel-3.10.0-1160.88.1.el7.x86_64
kernel-3.10.0-1160.83.1.el7.x86_64因为我们使用的内核是3.10.0-1160.92.1.el7.x86_64，一般来说内核需要kernel-、kernel-devel-、kernel-headers-+版本号的文件，我这里就是如下内核是正在运行的，不要删除：
kernel-3.10.0-1160.92.1.el7.x86_64
kernel-devel-3.10.0-1160.92.1.el7.x86_64
kernel-headers-3.10.0-1160.95.1.el7.x86_64我这个当前版本还少了个对应版本的kernel-headers-，所以系统是使用kernel-headers-3.10.0-1160.95.1.el7.x86_64，所以他不能删除。
2、下面我们就删除指定内核文件，使用如下命令：
yum remove kernel-tools-3.10.0-1160.95.1.el7.x86_64返回如下：
[root@wiki-hk-web ~]# yum remove kernel-tools-3.10.0-1160.95.1.el7.x86_64
Loaded plugins: fastestmirror
Resolving Dependencies
--> Running transaction check
---> Package kernel-tools.x86_64 0:3.10.0-1160.95.1.el7 will be erased
--> Finished Dependency Resolution
Dependencies Resolved
======================================================================================================================================
Package Arch Version Repository Size
======================================================================================================================================
Removing:
kernel-tools x86_64 3.10.0-1160.95.1.el7 @updates 337 k
Transaction Summary
======================================================================================================================================
Remove 1 Package
Installed size: 337 k
Is this ok [y/N]:这里我们可以看到只会卸载指定的文件，所以没啥问题，输入Y，确认删除。
如果出现
[root@wiki-hk-web ~]# yum remove kernel-headers-3.10.0-1160.95.1.el7.x86_64
Loaded plugins: fastestmirror
Resolving Dependencies
--> Running transaction check
---> Package kernel-headers.x86_64 0:3.10.0-1160.95.1.el7 will be erased
--> Processing Dependency: kernel-headers for package: glibc-headers-2.17-326.el7_9.x86_64
--> Processing Dependency: kernel-headers >= 2.2.1 for package: glibc-headers-2.17-326.el7_9.x86_64
--> Processing Dependency: kernel-headers >= 2.6.27-0.144.rc0.git2.fc10 for package: libdrm-devel-2.4.97-2.el7.x86_64
--> Running transaction check
---> Package glibc-headers.x86_64 0:2.17-326.el7_9 will be erased
--> Processing Dependency: glibc-headers for package: glibc-devel-2.17-326.el7_9.x86_64
--> Processing Dependency: glibc-headers = 2.17-326.el7_9 for package: glibc-devel-2.17-326.el7_9.x86_64
---> Package libdrm-devel.x86_64 0:2.4.97-2.el7 will be erased
--> Processing Dependency: pkgconfig(libdrm) >= 2.4.75 for package: mesa-libEGL-devel-18.3.4-12.el7_9.x86_64
--> Processing Dependency: pkgconfig(libdrm) >= 2.4.75 for package: mesa-libGL-devel-18.3.4-12.el7_9.x86_64
--> Running transaction check
---> Package glibc-devel.x86_64 0:2.17-326.el7_9 will be erased
--> Processing Dependency: glibc-devel for package: 4:perl-devel-5.16.3-299.el7_9.x86_64
--> Processing Dependency: glibc-devel >= 2.2.90-12 for package: gcc-4.8.5-44.el7.x86_64
---> Package mesa-libEGL-devel.x86_64 0:18.3.4-12.el7_9 will be erased
--> Processing Dependency: pkgconfig(egl) for package: cairo-devel-1.15.12-4.el7.x86_64
---> Package mesa-libGL-devel.x86_64 0:18.3.4-12.el7_9 will be erased
--> Running transaction check
---> Package cairo-devel.x86_64 0:1.15.12-4.el7 will be erased
---> Package gcc.x86_64 0:4.8.5-44.el7 will be erased
--> Processing Dependency: gcc = 4.8.5-44.el7 for package: gcc-c++-4.8.5-44.el7.x86_64
--> Processing Dependency: gcc = 4.8.5 for package: libtool-2.4.2-22.el7_3.x86_64
---> Package perl-devel.x86_64 4:5.16.3-299.el7_9 will be erased
--> Processing Dependency: perl-devel for package: 1:perl-ExtUtils-ParseXS-3.18-3.el7.noarch
--> Processing Dependency: perl-devel for package: perl-ExtUtils-Install-1.58-299.el7_9.noarch
--> Running transaction check
---> Package gcc-c++.x86_64 0:4.8.5-44.el7 will be erased
---> Package libtool.x86_64 0:2.4.2-22.el7_3 will be erased
---> Package perl-ExtUtils-Install.noarch 0:1.58-299.el7_9 will be erased
--> Processing Dependency: perl(ExtUtils::Install) for package: perl-ExtUtils-MakeMaker-6.68-3.el7.noarch
--> Processing Dependency: perl(ExtUtils::Installed) for package: perl-ExtUtils-MakeMaker-6.68-3.el7.noarch
--> Processing Dependency: perl(ExtUtils::Packlist) for package: perl-ExtUtils-MakeMaker-6.68-3.el7.noarch
---> Package perl-ExtUtils-ParseXS.noarch 1:3.18-3.el7 will be erased
--> Running transaction check
---> Package perl-ExtUtils-MakeMaker.noarch 0:6.68-3.el7 will be erased
--> Finished Dependency Resolution
Dependencies Resolved
======================================================================================================================================
Package Arch Version Repository Size
======================================================================================================================================
Removing:
kernel-headers x86_64 3.10.0-1160.95.1.el7 @updates 3.8 M
Removing for dependencies:
cairo-devel x86_64 1.15.12-4.el7 @base 2.2 M
gcc x86_64 4.8.5-44.el7 @base 37 M
gcc-c++ x86_64 4.8.5-44.el7 @base 16 M
glibc-devel x86_64 2.17-326.el7_9 @updates 1.0 M
glibc-headers x86_64 2.17-326.el7_9 @updates 2.2 M
libdrm-devel x86_64 2.4.97-2.el7 @base 543 k
libtool x86_64 2.4.2-22.el7_3 @base 2.2 M
mesa-libEGL-devel x86_64 18.3.4-12.el7_9 @updates 89 k
mesa-libGL-devel x86_64 18.3.4-12.el7_9 @updates 1.6 M
perl-ExtUtils-Install noarch 1.58-299.el7_9 @updates 75 k
perl-ExtUtils-MakeMaker noarch 6.68-3.el7 @base 635 k
perl-ExtUtils-ParseXS noarch 1:3.18-3.el7 @base 174 k
perl-devel x86_64 4:5.16.3-299.el7_9 @updates 1.8 M
Transaction Summary
======================================================================================================================================
Remove 1 Package (+13 Dependent packages)
Installed size: 70 M
Is this ok [y/N]:说明有的软件依赖于他，卸载的话，这些软件都会被卸载，为了谨慎起见，建议不要卸载。如果你已经下载了新的kernel-headers文件，这里也可以先卸载，然后安装新的kernel-headers文件，然后再把软件一个一个装回来。所以我建议VPS重装后第一件是是把内核更新了，然后再装软件。
排除后，我们又使用rpm -qa | grep kernel查看剩余内核，再使用yum remove[空格]内核名称来一个一个手动删除，手动删除的好处是可以保留需要的内核。
当然，也有自动命令，执行以下命令可以自动获取当前系统中的无用内核（未使用的）并进入卸载：
yum remove $(rpm -qa | grep kernel | grep -v $(uname -r))执行上面命令后，会有卸载确认操作。确认下卸载内核列表中没有当前正在使用的内核，然后输入y确认卸载即可。
3、卸载完毕后，可以执行以下命令查看下/boot分区的占用情况
df -h /boot返回如下
[root@wiki-hk-web ~]# df -h /boot
Filesystem Size Used Avail Use% Mounted on
/dev/vda1 50G 5.8G 45G 12% /