Setting Up VPN-like Network Between Several Clusters Using iptables

It is common to connect servers with only internal IPs from several clusters. VPN is a common technique for this. With iptables, we can implement many functions of VPN with possibly higher performance. The slides here give a brief introduction to how to set up a VPN-like network between 2 clusters which connect to each other through Internet. Note that this is not a “real” VPN. » Read more

Simple Introduction to paravirt_ops for Xen

The is a simple introduction to paravirt_ops in Linux kernel for Xen, VMware, etc. We make this introduction from the view of code. We use the function raw_local_irq_disable() and raw_local_irq_enable() functions in Linux kernel to introduce paravirt_ops for Xen and Xenified kernel. Please download the introduction to paravirt_ops pdf file: introduction-to-pv-ops-v3.pdf » Read more

An Introduction to Xen Source Code Structure and Disk in Xen

Please note these slides on Xen was made in around 2013 and the Xen source code structure might have already changed a lot. Please check this as a reference to the Xen source structure only. I have created slides from introducing Xen’s source code structure and backend and frontend drivers in Xen.Please find the PDF version here: xen-code-disk-v2.pdf There are animations in the PDF and you may enable them which may help to understand it. » Read more