Solution: Centos 6 upgrade prompt At least 16 MB more space needed on the/boot filesystem

Encountered error:

Transaction Check Error:
Installing package kernel-2.6.32-504.8.1.el6.x86_64 needs 16 MB on the/boot filesystem

Error Summary
-------------
Disk Requirements:
At least 16 MB more space needed on the/boot filesystem.

Check it out:

# Df-h
Filesystem Size Used Avail Use % Mounted on
/Dev/sda3 458 GB 214G 221G 50%/
Tmpfs 1.9G 0 1.9G 0%/dev/shm
/Dev/sda1 99 M 82 M 13 M 87%/boot

Solution: delete the old kernel.

1. View the currently used kernel

# Uname-r
2.6.32-431.1.2.0.1.el6.x86 _ 64

2. View the installed kernel in the system:

# Rpm-qa | grep kernel
Kernel-2.6.32-358.el6.x86_64
Abrt-addon-kerneloops-2.0.8-21.el6.centos.x86_64
Kernel-devel-2.6.32-358.6.1.el6.x86_64
Libreport-plugin-kerneloops-2.0.9-19.el6.centos.x86_64
Kernel-2.6.32-358.6.1.el6.x86_64
Kernel-devel-2.6.32-431.1.2.0.1.el6.x86_64
Dracut-kernel-004-336.el6_5.2.noarch
Kernel-firmware-2.6.32-431.1.2.0.1.el6.noarch
Kernel-headers-2.6.32-431.1.2.0.1.el6.x86_64
Kernel-2.6.32-431.1.2.0.1.el6.x86_64

Delete the old kernel:

# Yum remove kernel-2.6.32-358.el6.x86_64 kernel-2.6.32-358.6.1.el6.x86_64 kernel-devel-2.6.32-358.6.1.el6.x86_64

Check the/boot space again:

# Df-h | grep boot
/Dev/sda1 99 M 30 M 65 M 32%/boot