# systemctl start firewalld
Hello, my name is Dũng (Johnny). Welcome to my blog.
As I’m a developer, I write about topics related to the field of programming, mainly from a technical point of view. On this blog you’ll find posts which encourage discussion, information about development trends, case studies, reviews, tutorials, tips on how to improve your effectiveness, and anything else that might be fascinating to people from the IT industry.
I love PHP, NodeJS, Java,... and Fullstack.