Stopping VirtualBox kernel modules                         [  OK  ]
Uninstalling old VirtualBox DKMS kernel modules            [  OK  ]
Trying to register the VirtualBox kernel modules using DKMS
Error! Your kernel source for kernel 2.6.32-220.4.2.el6.x86_64 cannot be found at
/lib/modules/2.6.32-220.4.2.el6.x86_64/build or /lib/modules/2.6.32-220.4.2.el6.x86_64/source.
                                                           [СБОЙ ]
  (Failed, trying without DKMS)
Recompiling VirtualBox kernel modules                      [СБОЙ ]
  (Look at /var/log/vbox-install.log to find out what went wrong)
[root@server02 server02]#

В логе
Uninstalling modules from DKMS
  removing old DKMS module vboxhost version  4.1.8

------------------------------
Deleting module version: 4.1.8
completely from the DKMS tree.
------------------------------
Done.
Attempting to install using DKMS

Creating symlink /var/lib/dkms/vboxhost/4.1.8/source ->
                 /usr/src/vboxhost-4.1.8

DKMS: add Completed.
You can use the --kernelsourcedir option to tell DKMS where it's located.
Failed to install using DKMS, attempting to install without
Makefile:172: *** Error: unable to find the sources of your current Linux kernel. Specify KERN_DIR=<directory> and run Make again.  Останов.

kernel-devel установлен. Я даже переустановил его для верности. Не работает...
Куда копать?