Raghavendra Talur's blog

Theatricality and deception are powerful agents against the uninitiated. I was reminded of this line from Christopher Nolan's Batman series when I read about Tamil Nadu's farmers' protest in New Delhi. Their peaceful protest was filled with theatrics such as hold ing skulls of dead farmers in their hand and live rats in their mouth. Unfortunately, they have returned back to Tamil Nadu after 100 days with no demands met. This is because our politicians aren't uninitiated. Heck, no politician in the world is uninitiated. The very best example would be one Mr.Arvind Kejriwal who as a IIT graduate and a qualified IRS, came across as a honest man up against corruption and nothing else. Now, he is friends with likes of Lalu Prasad Yadav, Mamata Banerjee and is blatantly more power hungry than the seasoned politicians. There is very deep rooted misconception in India that being a politician is a selfless job. While we make the pact with our country that our responsibil

Today we debugged yet another issue which eventually turned out to a time synchronization problem with multiple machines. Let us first look at the case we solved today: The setup consisted of 3 nodes, 1 master OpenShift deployment. Whenever we started a privileged systemd container on a node, the node would enter into a NotReady state. These nodes were VMs that were hosted on a VMware EXSI server and the peculiarity was that the issue wasn't seen on a similar OpenShift setup hosted on a libvirt hypervisor. To truly understand the issue, you need to know about hardware clock and system clock. Hardware clock is maintained on the chip and powered by a battery for the duration when the system is shutdown. System clock is maintained by OS in memory. When the computer boots, OS picks up the time from Hardware clock and sets the system clock. To mitigate clock skew, system clock is updated by OS at regular intervals using ntp or chrony or similar services. Now, hardware clock does n