OCP images have different version tags like:
We should document the versioning policy to allow users to understand what are all these tags used for and which one to use for example when constructing the advanced installation inventory file.
Here is the policies for the versions:
latest - as well as no tag (which defaults to latest) :
**Users and scripts should not use the latest tag when dealing with openshift images**
Reason: There are many openshift images with the same name, but for different versions of openshift. When any of these images are uploaded to the registry, they are tagged 'latest'.
We still support older versions of OpenShift, so we are constantly updating those images. Thus, the image marked "latest" could be for a 3.3, 3.4 or 3.5 version.
Again, do not use the "latest" tag.
v3.5, v3.4, v3.3, - v<short-version number>
These tags are what users or scripts should use to get the latest image for a specific version of openshift.
In the example above, the v3.4 tag, currently points to 3.4-6. If we were to update the registry-console image, the v3.4 tag would change to point to that new tag (example: v3.4 -> 3.4-8)
Here is a different example that will help explain the other tags better than the above version.
3.3.0, 3.3.1, 3.4.0, 3.4.1 - <full version number>
This points to the latest image for that version. This gets changed with each update, just like the v3.4 does.
In the above example, 3.4.1 points to 3.4.1-6. If there was an update to 3.4.1, it would change to point to that tag. (example: 3.4.1 -> 3.4.1-8)
3.4.0-11, 3.4.1-2, 3.4.1-6 - <full version number>-<release number>
These tags are unique and do not change. 3.4.1-2 should always have the same shasum and should never change.
In short, these are the images/tags, that all other tags point to.
Thanks Troy, excellent info - I think the only missing piece anymore is the difference between v3.4 vs 3.4 (which actually seems to be present only for some images).
That's why I picked that second example.
In the original example 3.4 is the full version number, which makes it a little confusing because v3.4 is also pointing to the same thing.
Having examples with longer version numbers makes for better examples.
(In reply to Troy Dawson from comment #1)
> latest - as well as no tag (which defaults to latest) :
> **Users and scripts should not use the latest tag when dealing with
> openshift images**
> Reason: There are many openshift images with the same name, but for
> different versions of openshift. When any of these images are uploaded to
> the registry, they are tagged 'latest'.
> We still support older versions of OpenShift, so we are constantly updating
> those images. Thus, the image marked "latest" could be for a 3.3, 3.4 or
> 3.5 version.
> Again, do not use the "latest" tag.
We should underline that the above is specifically about OpenShift images; for example during containerized installation we still get rhel7/etcd:latest. Thanks.
I've created the following for this BZ:
Marko, Troy, can I ask for a review that this is what you're asking for?
But also, with using the `latest` tag, should we be advising against that altogether? When saying "don't use this with OpenShift images" can we get more specific?
As for being specific, I can't speak for more than the official OCP images, which start with openshift3/<name>
The other images coming from OpenShift Origin and CentOS, may, or may not be tagged in a similar fashion as OCP. But I believe they will still have a "latest" issue, unless they do some other way of tagging latest.
(In reply to brice from comment #8)
> I've created the following for this BZ:
I think this looks good, perhaps one sentence of the purpose / the need for having both vX.Y and X.Y.Z tags might be helpful but even without those this is very helpful. Thanks!
Thanks. I've updated the PR with a few more points. If you have any suggestions, please let me know.
Commit pushed to master at https://github.com/openshift/openshift-docs
Merge pull request #4374 from bfallonf/versions_1443588
Bug 1443588 Added info on image tag policy
Link to released docs: