Docker Engine v20.10 and up includes optimizations to verify if images in the
local image cache need updating before pulling, preventing the Docker Engine
from making unnecessary API requests. These optimizations require the container
image registry to conform to the Open Container Initiative Distribution Specification
(https://github.com/opencontainers/distribution-spec).
While most registries conform to the specification, we encountered some registries
to be non-compliant, resulting in `docker pull` to fail.
As a temporary solution, Docker Engine v20.10 includes a fallback mechanism to
allow `docker pull` to be functional when using a non-compliant registry. A
warning message is printed in this situation:
WARNING Failed to pull manifest by the resolved digest. This registry does not
appear to conform to the distribution registry specification; falling back to
pull by tag. This fallback is DEPRECATED, and will be removed in a future
release.
The fallback is added to allow users to either migrate their images to a compliant
registry, or for these registries to become compliant.
Note that this fallback only addresses failures on `docker pull`. Other commands,
such as `docker stack deploy`, or pulling images with `containerd` will continue
to fail.
Given that other functionality is still broken with these registries, we consider
this fallback a _temporary_ solution, and will remove the fallback in an upcoming
major release.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Looks like the YAML conversion doesn't like lines starting with `[`, and
causing it to use the "compact" formatting in the generated YAML.
This patch un-wraps these lines to prevent this.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
To create this, I ran every JSON document through `jq -S` (which sorts the keys and consistently pretty-prints the result in a format which matches the majority of documents in this file).
Signed-off-by: Tianon Gravi <admwiggin@gmail.com>
Docker v17.07 introduced an experimental `--stream` flag on `docker build` which
allowed the build-context to be incrementally sent to the daemon, instead of
unconditionally sending the whole build-context.
This functionality has been reimplemented as part of BuildKit, which uses streaming
by default and the `--stream` option will be ignored when using the classic builder,
printing a deprecation warning instead.
Users that want to use this feature are encouraged to enable BuildKit by setting
the `DOCKER_BUILDKIT=1` environment variable or through the daemon or CLI configuration
files.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The experimental feature to run Linux containers on Windows (LCOW) was introduced
as a technical preview in Docker 17.09. While many enhancements were made after
its introduction, the feature never reached completeness, and development has
now stopped in favor of running docker natively on Linux in WSL2.
Developers that need to run Linux workloads on a Windows host are encouraged
to use Docker Desktop with WSL2 instead.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The CLI disabled experimental features by default, requiring users
to set a configuration option to enable them.
Disabling experimental features was a request from Enterprise users
that did not want experimental features to be accessible.
We are changing this policy, and now enable experimental features
by default. Experimental features may still change and/or removed,
and will be highlighted in the documentation and "usage" output.
For example, the `docker manifest inspect --help` output now shows:
EXPERIMENTAL:
docker manifest inspect is an experimental feature.
Experimental features provide early access to product functionality. These features
may change between releases without warning or can be removed entirely from a future
release. Learn more about experimental features: https://docs.docker.com/go/experimental/
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Some deprecations are ammended during a major (YY.MM) release, to
inform users as early as possible about deprecations. Removing the
minor version from this overview clarifies that features are
marked deprecated during which major release's lifecycle.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
If a file contains trailing whitespace, the YAML generator uses a
compact format, which is hard to read.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The Dockerfile `ENV` instruction allows values to be set using either `ENV name=value`
or `ENV name value`. The latter (`ENV name value`) form can be ambiguous, for example,
the following defines a single env-variable (`ONE`) with value `"TWO= THREE=world"`,
but may have intended to be setting three env-vars:
ENV ONE TWO= THREE=world
This format also does not allow setting multiple environment-variables in a single
`ENV` line in the Dockerfile.
Use of the `ENV name value` syntax is discouraged, and may be removed in a future
release. Users are encouraged to update their Dockerfiles to use the `ENV name=value`
syntax, for example:
ENV ONE="" TWO="" THREE="world"
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The `ENV key value` form can be ambiguous, for example, the following defines
a single env-variable (`ONE`) with value `"TWO= THREE=world"`:
ENV ONE TWO= THREE=world
While we cannot deprecate/remove that syntax (as it would break existing
Dockerfiles), we should reduce exposure of the format in our examples.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
When creating and updating services, we need to avoid unneeded service churn.
The interaction of separate lists to "add" and "drop" capabilities, a special
("ALL") capability, as well as a "relaxed" format for accepted capabilities
(case-insensitive, `CAP_` prefix optional) make this rather involved.
This patch updates how we handle `--cap-add` / `--cap-drop` when _creating_ as
well as _updating_, with the following rules/assumptions applied:
- both existing (service spec) and new (values passed through flags or in
the compose-file) are normalized and de-duplicated before use.
- the special "ALL" capability is equivalent to "all capabilities" and taken
into account when normalizing capabilities. Combining "ALL" capabilities
and other capabilities is therefore equivalent to just specifying "ALL".
- adding capabilities takes precedence over dropping, which means that if
a capability is both set to be "dropped" and to be "added", it is removed
from the list to "drop".
- the final lists should be sorted and normalized to reduce service churn
- no validation of capabilities is handled by the client. Validation is
delegated to the daemon/server.
When deploying a service using a docker-compose file, the docker-compose file
is *mostly* handled as being "declarative". However, many of the issues outlined
above also apply to compose-files, so similar handling is applied to compose
files as well to prevent service churn.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The docker CLI up until v1.7.0 used the `~/.dockercfg` file to store credentials
after authenticating to a registry (`docker login`). Docker v1.7.0 replaced this
file with a new CLI configuration file, located in `~/.docker/config.json`. When
implementing the new configuration file, the old file (and file-format) was kept
as a fall-back, to assist existing users with migrating to the new file.
Given that the old file format encourages insecure storage of credentials
(credentials are stored unencrypted), and that no version of the CLI since
Docker v1.7.0 has created this file, the file is marked deprecated, and support
for this file will be removed in a future release.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The output format was changed to combine tag and name in a single
column, but this change was never reflected in the docs.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This reflects a Moby change to add documentation around
disabling a new feature -- to use pgzip to decompress
layers, rather than the built-in go gzip.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This creates a new section of environment variables in the CLI docs
which documents environment variables that can both be used on dockerd
and on docker cli.
In addition, it moves some of the environment variable documentation
from the docker cli documentation to the dockerd documentation, as
these environment variables are dockerd-specific.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The Engine API docs are not available in this GitHub repository,
so linking to the docs.docker.com website instead.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
- replace the "none" code-hint with "console"
- some changes in the "experimental" instructions
- reformat some notes
- reformat / re-indent JSON output to use 2 spaces (for consistency)
- split JSON outputs to separate code-block so that it can be highlighted
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This adds the currently selected "docker context" to the output
of "docker version", which allows users to see which context
is selected to produce the version output, and can be used (for
example), to set the prompt to the currently selected context:
(in `~/.bashrc`):
```bash
function docker_context_prompt() {
PS1="context: $(docker version --format='{{.Client.Context}}')> "
}
PROMPT_COMMAND=docker_context_prompt
```
After reloading the `~/.bashrc`, the prompt now shows the currently selected
`docker context`:
```bash
$ source ~/.bashrc
context: default> docker context create --docker host=unix:///var/run/docker.sock my-context
my-context
Successfully created context "my-context"
context: default> docker context use my-context
my-context
Current context is now "my-context"
context: my-context> docker context use default
default
Current context is now "default"
context: default>
```
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Using `/var/run/docker.sock` as docker host is invalid, and causes
an error, so adding `unix://` to it.
In addition, we document the name of the context to go after the
options, so change the order in the examples.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
1. Fix dead URL to [Dockerfile best practices](https://docs.docker.com/develop/develop-images/dockerfile_best-practices/#leverage-build-cache).
2. Add missing information about cache invalidation by `COPY`. It works in the same way as in the case of `ADD`. Informing only about the `ADD`s behavior is misleading as one can infer that these two directives differ in this regard.
3. Add missing info on RUN cache invalidation by COPY
Signed-off-by: Maciej Kalisz <maciej.d.kalisz@gmail.com>
This link was broken when generating the documentation (due to
a bug in Jekyll not converting wrapped internal links)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
* Added two new modes accepted by the `--mode` flag
* `replicated-job` creates a replicated job
* `global-job` creates a global job.
* When using `replicated-job` mode, the `replicas` flag sets the
`TotalCompletions` parameter of the job. This is the total number of
tasks that will run
* Added a new flag, `max-concurrent`, for use with `replicated-job`
mode. This flag sets the `MaxConcurrent` parameter of the job, which
is the maximum number of replicas the job will run simultaneously.
* When using `replicated-job` or `global-job` mode, using any of the
update parameter flags will result in an error, as jobs cannot be
updated in the traditional sense.
* Updated the `docker service ls` UI to include the completion status
(completed vs total tasks) if the service is a job.
* Updated the progress bars UI for service creation and update to
support jobs. For jobs, there is displayed a bar covering the overall
progress of the job (the number of tasks completed over the total
number of tasks to complete).
* Added documentation explaining the use of the new flags, and of jobs
in general.
Signed-off-by: Drew Erny <derny@mirantis.com>
Service create expects the name to be passed using the
`--name` flag, not as a positional parameter
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Currently the documentation uses a special case for this command,
so adding a description to the YAML in order to remove that
special case.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Colon may not be something non-native English readers
know about, so explain the symbol in the running text.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
- add code-fences with code-hints so that the right hightlighting is applied
- replace `*` for `-` in bullet-lists for consistency with other parts of the
documentation.
- reduced number of "notes", either by combining some, or by changing some
to regular text.
- removed "line numbers" from some examples, because there's only four lines,
which should not need really need line numbers.
- reformat some notes to our new format
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
- add code-fences with code-hints so that the right
hightlighting is applied
- reduced number of "notes", either by combining some,
or by changing some to regular text.
- use tables for some option lists
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
- fix various broken links
- fix incorrect anchors
- updated links for content that moved, so that no
redirect to the new location is needed.
- touched-up Markdown;
- re-format some JSON output
- add blank line betweeen command and command output
- format "note" blocks
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The `docker network prune` command removes unused custom networks,
but built-in networks won't be removed. This patch updates the
message to mention that it's only removing custom networks.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Silvin Lubecki
Sebastiaan van Stijn
Sebastiaan van Stijn
Andres Leon Rangel
Benjamin Böhmke
Kyle
Tianon Gravi
Eric Engestrom
Charlotte Mach
Tibor Vass
Albin Kerouanton
horpto
eyherabh
Tonis Tiigi
Akihiro Suda
Brian Wieder
dito
Saswat Bhattacharya
Sargun Dhillon
Justin Cormack
Simon Heimberg
devisions
Silvin Lubecki
Maciej Kalisz
Drew Erny
Dominik Braun
Hector S