Upgrades! Sometimes they are a lot of homework.
Enabled Centos-Plus repos and elrepo for recent kernels. I figured out I want to install kernel-ml, kernel-ml-headers, kernel-ml-devel. That last one escaped me but is necessary because you need it when you do a dkms install.
So after updating that stuff, I was able to dkms install spl/0.6.5.3, dkms install zfs/0.6.5.3. I also made sure to modprobe spl zfs. Linked /usr/lib/systemd/system/zfs.target into /etc/systemd/system/sysinit.target.wants. Reboot. Make sure zfs pool returns.
To get vboxdrv all working I needed to make sure I installed the vboxdriver. That is /usr/sbin/rcvboxdrv. Easy to forget, that’s rather new. Then (as root) do a vboxmanage extpack install ~/Downloads/VirtualBox-extpack-5.0.6.extpack and that will keep your guest vms from blocking on missing USB-UHCI drivers.
Then go back and read my prev post on updating grub. I kept booting into kernel 3.10.x and wondering why grub2-install /dev/sda wasn’t doing it’s job. Ubuntu did the right amount of work with the update-grub2 script, I’ll say.