生产服务器：
OS：CentOS 6.8
任务：yum upgrade #升级软件包，但不更改软件和系统配置，不升级内核。
问题：
运行 rpm_check_debug
执行事务测试
事务测试出错：
installing package kernel-2.6.32-642.11.1.el6.x86_64 needs 15MB on the /boot filesystem
出错情况
-------------
磁盘要求：
At least 15MB more space needed on the /boot filesystem.
[[email protected] /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 49G 22G 25G 48% /
tmpfs 939M 44K 939M 1% /dev/shm
/dev/sda1 93M 75M 14M 85% /boot
/dev/sda5 179G 1.8G 168G 2% /home
解决方法：删除旧版的kernel
[[email protected] /]# rpm -qa|grep kernel
dracut-kernel-004-409.el6_8.2.noarch
kernel-2.6.32-504.1.3.el6.x86_64
kernel-firmware-2.6.32-642.el6.noarch
kernel-devel-2.6.32-573.12.1.el6.x86_64
kernel-2.6.32-573.12.1.el6.x86_64
kernel-2.6.32-642.el6.x86_64
kernel-devel-2.6.32-642.el6.x86_64
kernel-headers-2.6.32-642.el6.x86_64
[[email protected] /]# yum remove kernel-2.6.32-504.1.3.el6.x86_64 kernel-devel-2.6.32-573.12.1.el6.x86_64 kernel-2.6.32-573.12.1.el6.x86_64 kernel-devel-2.6.32-642.el6.x86_64 kernel-headers-2.6.32-642.el6.x86_64
............
删除完毕！
[[email protected] /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 49G 22G 25G 47% /
tmpfs 939M 44K 939M 1% /dev/shm
/dev/sda1 93M 28M 61M 32% /boot #可用空间61M
/dev/sda5 179G 1.8G 168G 2% /home
[[email protected] /]# yum upgrade #升级软件包
[[email protected] /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 49G 22G 25G 47% /
tmpfs 939M 44K 939M 1% /dev/shm
/dev/sda1 93M 54M 35M 61% /boot #升级软件包之后，可用空间只可用35M
/dev/sda5 179G 1.8G 168G 2% /home