As the popularity of virtual machines increases so does the amount of data that we store in them. Often we may generate data within virtual machines environments as a result of applications running within them. Due to this many virtual machine monitor vendors provides methods for transferring data between a running virtual machine (Guest OS) and the host machine (Host OS). This is the most common method and normally the most useful for frequent virtual machine users.

Recently I purchased a larger hard-drive for my laptop. In purchasing this I definately didn’t want to have to rebuild my system from scratch and such looked into some approaches for moving my multiple operating systems and my data to the new drive without having to rebuild either operating systems from scratch. My old hard-drive contained four partitions, first partition was a recovery partition, the second partition was my main partition containing Windows Vista, the third partition was linux swap space for my fourth partition which contained Ubuntu. Grub was located on this final partition, however the boot record was contained in the first partition.

During the work on our industry project we came across the need to have an Document class that contains the common header information for documents and we needed this to reference a specific document such as Process, Report, etc. This is a form of inheritance and in ROR there a many ways of achieiving this. The first way is using single table inheritance which is what we wanted to avoid as this data model would be penalised using this architecture.