Unknown option when running mix release

Question

I've just upgraded Elixir from 1.7.4 to 1.10.4 on my build server and I'm getting this error:

** (Mix) Could not invoke task "release": 2 errors found!
--env : Unknown option
--no-tar : Unknown option

The command remained the same as before, which is:

MIX_ENV=prod mix release --env=prod --no-tar

When I try to run without these two flags the build works but I can't get the server running. These are the errors.

{"could not start kernel pid",application_controller,"error in config file \"/mokily/gerard/releases/222.38.10/sys.config\" (none): configuration file not found"}

could not start kernel pid (application_controller) (error in config file "/mokily/gerard/releases/222.38.10/sys.config" (none): configuration file not found)

Answer 1

1. These flags are not needed for release. env is already specified by MIX_ENV=prod, tar won’t be built.
2. Before issuing mix release one must prepare the source tree to release with mix release.init.