Logstash is a pipeline for data ingesting, filtering and transformation. It is written using JRuby and Java. So It is quite a headache to navigate between Ruby code and Java code. In Logstash, ther...

vector is a combination of filebeat and logstash. VRL syntax See blog https://vector.dev/guides/level-up/transformation/ The . acts as a sort of “container” for the event data. . by itself re...

Filebeat is probably the most popular beat of all the beats provided by Elastic. The repo is very large containing over 1M+ lines of code. I will gradually add learning notes about this repo. Metr...

Memory Resource Controller When you exec into a k8s pod, you will find a lot of files under /sys/fs/cgroup/memory. root@kafka-all-in-one-consumer-7567f685c4-8wv8x:/sys/fs/cgroup/memory# ls -l tot...

Envoy is a proxy solution. There are so many proxies in the market: nginx, haproxy, trafik and etc, but why does Envoy stand out? It is because the xDS APIs, or a fancier name, xDS protocol. Envoy ...

Istio used to have a micro-service architecture. However, starting from v1.5, It moved back to a monolithic architecture. This largely simplifies the management of Istio. After v1.5, we only need t...

The purpose of vacuum: recover disk space. Update planner statistics Prevent transaction id wraparound failure how dd dashboard show low row count after failover ...

Jenkins has a master-agent architecture. Agent, i.e., worker is also called “node” in Jenkins terminology. Master distributes jobs to agents. Agent vs inbound agent You may wonder why there are t...

Jenkins pipeline Jenkins pipeline is probably the most important concept that a newbie needs to learn. Whenever you write a Jenkinsfile, you write a pipeline. When I started to use and learn Jenki...

We are all familiar with the concept of role based authorization. It is designed around answering this question: is role X allowed to do Y on object Z? Postgres is no exception. How to allow multi...