It would be better IMO to just copy the alertmanager.yml file into the /tmp folder in the Dockerfile and have the entrypoint perform the file modifications as a part of the copy.
If I try and add a docker config file to the path /etc/alertmanager/alertmanager.yml i get the error
mv: can't rename '/tmp/alertmanager.yml': Device or resource busy
It would be better IMO to just copy the alertmanager.yml file into the /tmp folder in the Dockerfile and have the entrypoint perform the file modifications as a part of the copy.
If I try and add a docker config file to the path /etc/alertmanager/alertmanager.yml i get the error