Virtualization

User Mode Linux 5.2

User Mode Linux version 5.2 has been uploaded to Debian Unstable and will soon be available on the supported architectures. This upload took more time than usual as I ran into a build time failure caused by newer PCAP library.

Thanks to active upstream developers, this got sorted out quick. In the longer run, we may have a much better fix for it.

What is User Mode Linux a.k.a uml

It is one of the initial virtualization technologies that Linux provided, which still works and is supported/maintained. It is about running a Linux kernel as a single unprivileged user process.

Linux and ARM

With more ARM based devices in the market, and with them getting more powerful every day, it is more common to see more of ARM images for your favorite Linux distribution. Of them, Debian has become the default choice for individuals and companies to base their work on. It must have to do with Debian’s long history of trying to support many more architectures than the rest of the distributions. Debian also tends to have a much wider user/developer mindshare even though it does not have a direct backing from any of the big Linux distribution companies.

Linux has improved many many things over the last couple of years. Of the many improvements, the one that I’ve started leveraging the most today, are Control Groups.

In the past, when there was a need to build a prototype for a solution, we needed hardware.

Then came the virtualization richness to Linux. It came in 2 major flavors, KVM ( Full Virtualization ) and Xen ( Para Virtualization ). Over the years, the difference of para vs full, for both the implementations, is almost none. KVM now has support for Para-Virtualizaiton, with para-virtualized drviers for most resource intensive tasks, like network and I/O. Similarly, Xen has Full Virtualization support with the help of Qemu-KVM.