/ partição de inicialização completa no centos 7

Question

Não consigo yum update porque a minha partição /boot já está cheia (instalei o CentOS há 3 meses).

Eu não sei o que excluir para fazer algum lugar em / boot.

Aqui, um ls -la de /boot :

-rw-r--r--. 1 root root   126431 Oct 24 18:18 config-3.10.0-327.36.3.el7.x86_64
-rw-r--r--  1 root root   137700 Dec  7 00:18 config-3.10.0-514.2.2.el7.x86_64
-rw-r--r--  1 root root   137700 Jan 18 14:17 config-3.10.0-514.6.1.el7.x86_64
drwxr-xr-x. 2 root root     1024 Dec  6 21:14 grub
drwx------. 6 root root     1024 Jan 31 19:02 grub2
-rw-r--r--. 1 root root 45965414 Dec  6 21:21 initramfs-0-rescue-8ef430d24c10480fa3b14afff578664c.img
-rw-------  1 root root 17088683 Jan 11 14:46 initramfs-3.10.0-327.36.3.el7.x86_64.img
-rw-------  1 root root 15408193 Jan  2 23:34 initramfs-3.10.0-327.36.3.el7.x86_64kdump.img
-rw-------  1 root root 17125483 Jan 11 14:47 initramfs-3.10.0-514.2.2.el7.x86_64.img
-rw-------  1 root root 15446676 Jan  3 00:32 initramfs-3.10.0-514.2.2.el7.x86_64kdump.img
-rw-------  1 root root 17123812 Jan 31 19:02 initramfs-3.10.0-514.6.1.el7.x86_64.img
-rw-------  1 root root 15443502 Jan 31 19:05 initramfs-3.10.0-514.6.1.el7.x86_64kdump.img
-rw-r--r--. 1 root root   614543 Jan  2 23:36 initrd-plymouth.img
drwx------. 2 root root    12288 Dec  6 21:10 lost+found
-rw-r--r--. 1 root root   252739 Oct 24 18:21 symvers-3.10.0-327.36.3.el7.x86_64.gz
-rw-r--r--  1 root root   277953 Dec  7 00:20 symvers-3.10.0-514.2.2.el7.x86_64.gz
-rw-r--r--  1 root root   277953 Jan 18 14:20 symvers-3.10.0-514.6.1.el7.x86_64.gz
-rw-------. 1 root root  2965270 Oct 24 18:18 System.map-3.10.0-327.36.3.el7.x86_64
-rw-------  1 root root  3113323 Dec  7 00:18 System.map-3.10.0-514.2.2.el7.x86_64
-rw-------  1 root root  3113404 Jan 18 14:17 System.map-3.10.0-514.6.1.el7.x86_64
-rwxr-xr-x. 1 root root  5158864 Dec  6 21:22 vmlinuz-0-rescue-8ef430d24c10480fa3b14afff578664c
-rwxr-xr-x. 1 root root  5158864 Oct 24 18:18 vmlinuz-3.10.0-327.36.3.el7.x86_64
-rwxr-xr-x  1 root root  5393328 Dec  7 00:18 vmlinuz-3.10.0-514.2.2.el7.x86_64
-rwxr-xr-x  1 root root  5392752 Jan 18 14:17 vmlinuz-3.10.0-514.6.1.el7.x86_64