After downgrading Docker from 18.09 to 18.06 in EKS nodes using yum, the ES pod on the node goes into crash-loop with the following error in the logs:
max file descriptors [4096] for elasticsearch process is too low, increase to at least [65536]I do not think that this is because of Docker version, but because of default settings of the package. Adding fs.file-max=65536 to /etc/sysctl.conf did not help. Also, there is nothing especial in /etc/docker/daemon.json.
I found the settings in this file: /etc/sysconfig/docker
It is as follows:
OPTIONS="--default-ulimit nofile=1024:4096"By commenting out that line, the issue was resolved.