I had 30+ applications that were running on Rancher (1.x) in a docker-composed way. The logging of the applications (those were running inside the container) was done in such a way that no app logs get stored on the container or on the system but they directly got pushed to Graylog using GELF.
logging:
driver: gelf
options:
gelf-address: udp://hostname.com:port
tag: my-app
Now We plan to move our applications to new Rancher(2.x) which is based on kubernetes and thus have to change application compose files to k8s Deployments. However, I am not sure how to achieve the same thing in kubernetes.
I didn't get anything similar to the above snippet that could be used in Deployment files and then I started with fluentd to collect logs but as mentioned no app logs are available on the system or the container thus no luck with fluentd.
Looking for some suggestions.