A marathon app fails to deploy with
docker -H unix:///var/run/docker.sock pull repo.ops.sparklepony.com:8082/parser-docker:0.0.22': exit status = exited with status 1 stderr
Review the environment variables on
1. A node and user that can successfully pull a Docker image.
2. dcos-mesos-slave systemd unit file (in /etc/systemd) on an affected node.
3. Review your app definition - a user may have hardcoded credentials into the app definition, their permissions key may have changed since last deployment.
Provided the above checklist is correct your app should deploy.