After looking at several deployments of VMWare, we had one deployment where the company enabled balloon mode which is essentially a way to overcommit memory the hostnode(s) don't have. Let's say you have put your database into memory or use a cached service in Apache or haproxy/nginx. VMWare will start taking some portions of these and at some point it corrupts things and the application running will either crash, malfunction or segfault. Another factor is that OOMwill be........

It is possible to tell mdadm to create an md device on a raw disk even though it will give you an error, it writes a superblock and this corrupts the partition table which can result in your system not booting. To fix it just zero the super-block on the offending device that you made the mistake in. Eg: /dev/sda mdadm --zero-superblock /dev/sda It is also a way of starting fresh if you wanted to create a new array.........