virtualbox.org

I keep getting regular crashes on a couple systems. Often when they crash the same 3 systems crash together and when I try to get them online it often crashes the other ones that are online of the 3 that crash.
The other systems work normally, I tried copying the config from working system to a broke one with no success.

The guest for the attached logs is Microsoft Windows Server 2012 Standard
I think all the problematic systems are Windows 2012 or 2012 R2

You may have an issue with lack of memory on the host to support the VMs. Linux Out-of-Memory Killer may be kicking in - or rather kicking out your VMs.

I would also try enabling USB2 support, or disable USB support altogether.

I've been looking for Ubuntu 14.04LTS guest crashing on updates, this is closest hit I've found so far. There are tons of Ubuntu rant sites out there,,,ugh. Problem I have with Ubuntu 14.04LTS installed as a guest on an Arch Linux host running latest Arch kernel (custom ck-piledriver kernel actually and its respective v~box-ck-host-modules) and VirtualBox 5.0.22, is that when Ubuntu wants to install a huge major update, it crashes after rebooting the guest (required update completion). It has done this as far back as 4.0.8 that I recall. I keep regular rsync'd backup of the vdi so nothing is lost, and when I need to do a major Ubuntu update, i delete the running one and do a fresh install of the later version (due 2017 from what I understand of 14.04LTS).

Edit: Ubuntu 14.04 LTS successfully updated tonight via command line: Updating via the GUI fails, either fails to update with bogus error about network connection or other errors, or crashes after update when GUI completes the update - the crash is: the system does not boot up normal, either screen resolution is way off and will not respond to corrections if it boots up, or won't boot up at all. Perhaps the proper method is cli updates.