Where I work, we are migrating our entire infrastructure which was until now based on monolithic services that ran directly on a windows/linux VM to a docker based architecture that will be orchestrated by Kubernetes.

One of the things that came to my mind is how we would handle logs in this new infrastructure. Up until now, each app had its own way of handling logs, some were using log4net/log4j to write to file system, some were writing to GrayLog via a dedicated library.

The main problem I have with that is that one of the core ideas of programming micro-services in a Docker environment is that every service should assume as little as possible about the rest of services or the platform.

So basically I was looking into how I can abstract the logging process from the application, make it independent from the rest of the infrastructure.

One interesting thing that I found was that you could write the logs to standard output (stdout) and then configure Kubernetes to pull these logs and direct them to a centralised storage or a centralised logging server (like GrayLog) https://kubernetes.io/docs/concepts/cluster-administration/logging/

I have several concerns with this approach, for once, I haven't seen too many companies that do it, most popular logging solutions are to use a dedicated library to log to filesystem.

I am also concerned about how it might impact performance, some languages block if you write to stdout, whereas when you use a standard logging library, the logs are queued. So what about services that output massive amount of user related logs?

I was interested about what you think, I didn't see this approach used widely, maybe there is reason for that.