Rancher-EBS volumes hang on "Attaching"

In my setup I have two hosts, a multipurpose host and a support host within one environment. I am able to create the rancher-ebs service without issue on the support host.

However, when I try to create a stack with volumes using EBS, the services within the newly created stack just hang on ‘Activating,’ waiting for the newly created volume to attach. I can see that the volume has been created within EC2, it’s just currently stuck in attaching (16 minutes as of writing this).

I have tried using rancher-ebs attach directly to the ebs container with a docker exec, to the same results … Just hangs forever.

This is the only log I’ve gotten out of the EBS container since starting:
4/4/2017 1:58:42 PMtime="2017-04-04T18:58:42Z" level=info msg=create.request name="foo" options=map[size:50 volumeType:gp2 name:foo]