Docker (under boot2docker) does not look for/find

问题:

I'm running Docker on OS X under boot2docker 1.3.1

I built myself an image, oceania/python:

$ docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             VIRTUAL SIZE
oceania/python      0.1                 800229a896ff        16 hours ago        510.4 MB

I have another Dockerfile now where I want to use FROM oceania/python

When I try to build this image I get:

Sending build context to Docker daemon 31.74 MB
Sending build context to Docker daemon
Step 0 : FROM oceania/python
Pulling repository oceania/python
2014/11/20 17:23:51 Error: image oceania/python not found

Shouldn't it look at my local images first before going online to try and pull it?

Am I really obliged to upload it to a repository?

@jpetazzo answers here that what I am doing should work:
https://stackoverflow.com/a/20501690/202168

I assume the problem may therefore be boot2docker related

回答1:

Uhhh, ok...

It seems I have to include the tag, i.e.

FROM oceania/python:0.1

...then it works.

The docs appear to allow a FROM directive without the tag, and they say: "If no tag is given to the FROM instruction, latest is assumed."

I guess the underlying problem is that if your image is not uploaded to an index somewhere then it can't resolve 'latest' to a tag.

Another thing that's confusing is it seems in other people's answers and comments on similar issue, eg automated docker build run error: Unable to find image they get some output that looks like:

Unable to find image 'foo/bar:baz' locally

but in my output there's nothing to say docker even tried to look locally