# 内核

经过测试一般Ubuntu要三个内核并存，如果一个内核启动出错就用另一个启动。

```bash
#查看当前系统的内核版本
uname -a

Linux XT2000 4.15.0-169-generic #177-Ubuntu SMP Thu Feb 3 10:50:38 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

#查看所有的内核版本，可以看到下面有三个内核分别是4.15.0-163、4.15.0-166、4.15.0-169
dpkg --get-selections | grep linux

binutils-x86-64-linux-gnu                       install
console-setup-linux                             install
libselinux1:amd64                               install
linux-base                                      install
linux-firmware                                  install
linux-generic                                   install
linux-headers-4.15.0-163                        install
linux-headers-4.15.0-163-generic                install
linux-headers-4.15.0-166                        install
linux-headers-4.15.0-166-generic                install
linux-headers-4.15.0-169                        install
linux-headers-4.15.0-169-generic                install
linux-headers-generic                           install
linux-image-4.15.0-142-generic                  deinstall
linux-image-4.15.0-143-generic                  deinstall
linux-image-4.15.0-144-generic                  deinstall
linux-image-4.15.0-147-generic                  deinstall
linux-image-4.15.0-151-generic                  deinstall
linux-image-4.15.0-153-generic                  deinstall
linux-image-4.15.0-154-generic                  deinstall
linux-image-4.15.0-156-generic                  deinstall
linux-image-4.15.0-158-generic                  deinstall
linux-image-4.15.0-159-generic                  deinstall
linux-image-4.15.0-161-generic                  deinstall
linux-image-4.15.0-162-generic                  deinstall
linux-image-4.15.0-163-generic                  install
linux-image-4.15.0-166-generic                  install
linux-image-4.15.0-169-generic                  install
linux-image-generic                             install
linux-libc-dev:amd64                            install
linux-modules-4.15.0-142-generic                deinstall
linux-modules-4.15.0-143-generic                deinstall
linux-modules-4.15.0-144-generic                deinstall
linux-modules-4.15.0-147-generic                deinstall
linux-modules-4.15.0-151-generic                deinstall
linux-modules-4.15.0-153-generic                deinstall
linux-modules-4.15.0-154-generic                deinstall
linux-modules-4.15.0-156-generic                deinstall
linux-modules-4.15.0-158-generic                deinstall
linux-modules-4.15.0-159-generic                deinstall
linux-modules-4.15.0-161-generic                deinstall
linux-modules-4.15.0-162-generic                deinstall
linux-modules-4.15.0-163-generic                install
linux-modules-4.15.0-166-generic                install
linux-modules-4.15.0-169-generic                install
linux-modules-extra-4.15.0-142-generic          deinstall
linux-modules-extra-4.15.0-143-generic          deinstall
linux-modules-extra-4.15.0-144-generic          deinstall
linux-modules-extra-4.15.0-147-generic          deinstall
linux-modules-extra-4.15.0-151-generic          deinstall
linux-modules-extra-4.15.0-153-generic          deinstall
linux-modules-extra-4.15.0-154-generic          deinstall
linux-modules-extra-4.15.0-156-generic          deinstall
linux-modules-extra-4.15.0-158-generic          deinstall
linux-modules-extra-4.15.0-159-generic          deinstall
linux-modules-extra-4.15.0-161-generic          deinstall
linux-modules-extra-4.15.0-162-generic          deinstall
linux-modules-extra-4.15.0-163-generic          install
linux-modules-extra-4.15.0-166-generic          install
linux-modules-extra-4.15.0-169-generic          install
linux-sound-base                                install
pptp-linux                                      install
syslinux                                        install
syslinux-common                                 install
syslinux-legacy                                 install
util-linux                                      install

# 可以删除多余的不用的内核
sudo apt-get purge linux-headers-3.0.0-12 linux-image-3.0.0-12-generic

#更新grub引导
sudo update-grub
```


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