Custom script for modification to /etc/hosts. Providing custom /etc/hosts when building the image doesn't work because docker overwrites /etc/hosts when starting the container. Running simple "sed -i" inside entrypoint run script doesn't work because sed is not able to just overwrite /etc/hosts (sed: cannot rename /etc/sedl8ySxL: Device or resou…

docker_etc_hosts.sh

#!/usr/bin/env bash

# clean-up /etc/hosts if multiple hostname points to localhost - required for Mac OS using "--add-host 'localhost:10.0.2.2'"
localhostCount=`grep localhost /etc/hosts | wc -l`
if [[ $localhostCount -gt 2 ]];then
  cat /etc/hosts | sed '/127.0.0.1.*/d' > hosts.tmp
  cat hosts.tmp > /etc/hosts
  rm hosts.tmp
fi