This document describes the latest changes, additions, known issues, and fixesfor Docker Engine.
Note:The client and container runtime are now in separate packages from the daemonin Docker Engine 18.09. Users should install and update all three packages atthe same time to get the latest patch releases. For example, on Ubuntu:sudo apt install docker-ce docker-ce-cli containerd.io
. See the installinstructions for the corresponding linux distro for details.
Therefore the Docker daemon always runs as the root user and to run the docker command, you need to use sudo. Besides, during the Docker package installation, a group called docker is created. When the Docker daemon starts, it creates a UNIX socket accessible by members of the docker group (which grants privileges equivalent to the root user). A minimal Ubuntu base image modified for Docker-friendliness. Baseimage-docker only consumes 8.3 MB RAM and is much more powerful than Busybox or Alpine. Baseimage-docker is a special Docker image that is configured for correct use within Docker containers. It is Ubuntu, plus: Modifications for Docker-friendliness.
There are two methods for installing Docker on Ubuntu 16.04. One method involves installing it on an existing installation of the operating system. The other involves spinning up a server with a tool called Docker Machine that auto-installs Docker on. Update: 2018-09-10 The reason for choosing ufw-user-forward, not ufw-user-input using ufw-user-input. Pro: Easy to use and understand, supports older versions of Ubuntu. For example, to allow the public to visit a published port whose container port is 8080, use the command. We would like to show you a description here but the site won’t allow us.
20.10.5
2021-03-02
Client
- Revert docker/cli#2960 to fix hanging in
docker start --attach
and remove spuriousUnsupported signal: <nil>. Discarding
messages. docker/cli#2987.
20.10.4
2021-02-26
Builder
- Fix incorrect cache match for inline cache import with empty layers moby/moby#42061
- Update BuildKit to v0.8.2 moby/moby#42061
- resolver: avoid error caching on token fetch
- fileop: fix checksum to contain indexes of inputs preventing certain cache misses
- Fix reference count issues on typed errors with mount references (fixing
invalid mutable ref
errors) - git: set token only for main remote access allowing cloning submodules with different credentials
- Ensure blobs get deleted in /var/lib/docker/buildkit/content/blobs/sha256 after pull. To clean up old state run
builder prune
moby/moby#42065 - Fix parallel pull synchronization regression moby/moby#42049
- Ensure libnetwork state files do not leak moby/moby#41972
Client
- Fix a panic on
docker login
if no config file is present docker/cli#2959 - Fix
WARNING: Error loading config file: .dockercfg: $HOME is not defined
docker/cli#2958
Runtime
- docker info: silence unhandleable warnings moby/moby#41958
- Avoid creating parent directories for XGlobalHeader moby/moby#42017
- Use 0755 permissions when creating missing directories moby/moby#42017
- Fallback to manifest list when no platform matches in image config moby/moby#42045moby/moby#41873
- Fix a daemon panic on setups with a custom default runtime configured moby/moby#41974
- Fix a panic when daemon configuration is empty moby/moby#41976
- Fix daemon panic when starting container with invalid device cgroup rule moby/moby#42001
- Fix userns-remap option when username & UID match moby/moby#42013
- static: update runc binary to v1.0.0-rc93 moby/moby#42014
Logger
- Honor
labels-regex
config even iflabels
is not set moby/moby#42046 - Handle long log messages correctly preventing awslogs in non-blocking mode to split events bigger than 16kB mobymoby#41975
Rootless
- Prevent the service hanging when stopping by setting systemd KillMode to mixed moby/moby#41956
- dockerd-rootless.sh: add typo guard moby/moby#42070
- Update rootlesskit to v0.13.1 to fix handling of IPv6 addresses moby/moby#42025
- allow mknodding FIFO inside userns moby/moby#41957
Security
- profiles: seccomp: update to Linux 5.11 syscall list moby/moby#41971
Swarm
- Fix issue with heartbeat not persisting upon restart moby/moby#42060
- Fix potential stalled tasks moby/moby#42060
- Fix
--update-order
and--rollback-order
flags when only--update-order
or--rollback-order
is provided docker/cli#2963 - Fix
docker service rollback
returning a non-zero exit code in some situations docker/cli#2964 - Fix inconsistent progress-bar direction on
docker service rollback
docker/cli#2964
20.10.3
2021-02-01
Security
- CVE-2021-21285 Prevent an invalid image from crashing docker daemon
- CVE-2021-21284 Lock down file permissions to prevent remapped root from accessing docker state
- Ensure AppArmor and SELinux profiles are applied when building with BuildKit
Client
- Check contexts before importing them to reduce risk of extracted files escaping context store
- Windows: prevent executing certain binaries from current directory docker/cli#2950
20.10.2
2021-01-04
Runtime
- Fix a daemon start up hang when restoring containers with restart policies but that keep failing to start moby/moby#41729
- overlay2: fix an off-by-one error preventing to build or run containers when data-root is 24-bytes long moby/moby#41830
- systemd: send
sd_notify STOPPING=1
when shutting down moby/moby#41832
Networking
- Fix IPv6 port forwarding moby/moby#41805moby/libnetwork#2604
Swarm
- Fix filtering for
replicated-job
andglobal-job
service modes moby/moby#41806
Packaging
- buildx updated to v0.5.1docker/docker-ce-packaging#516
20.10.1
2020-12-14
Builder
- buildkit: updated to v0.8.1 with various bugfixes moby/moby#41793
Packaging
- Revert a change in the systemd unit that could prevent docker from starting due to a startup order conflict docker/docker-ce-packaging#514
- buildx updated to v0.5.0docker/docker-ce-packaging#515
20.10.0
2020-12-08
Deprecation / Removal
For an overview of all deprecated features, refer to the Deprecated Engine Features page.
- Warnings and deprecation notice when
docker pull
-ing from non-compliant registries not supporting pull-by-digest docker/cli#2872 - Sterner warnings and deprecation notice for unauthenticated tcp access moby/moby#41285
- Deprecate KernelMemory (
docker run --kernel-memory
) moby/moby#41254docker/cli#2652 - Deprecate
aufs
storage driver docker/cli#1484 - Deprecate host-discovery and overlay networks with external k/v stores moby/moby#40614moby/moby#40510
- Deprecate Dockerfile legacy ‘ENV name value’ syntax, use
ENV name=value
instead docker/cli#2743 - Remove deprecated “filter” parameter for API v1.41 and up moby/moby#40491
- Disable distribution manifest v2 schema 1 on push moby/moby#41295
- Remove hack MalformedHostHeaderOverride breaking old docker clients (<= 1.12) in which case, set
DOCKER_API_VERSION
moby/moby#39076 - Remove “docker engine” subcommands docker/cli#2207
- Remove experimental “deploy” from “dab” files docker/cli#2216
- Remove deprecated
docker search --automated
and--stars
flags docker/cli#2338 - No longer allow reserved namespaces in engine labels docker/cli#2326
API
- Update API version to v1.41
- Do not require “experimental” for metrics API moby/moby#40427
GET /events
now returnsprune
events after pruning resources have completed moby/moby#41259- Prune events are returned for
container
,network
,volume
,image
, andbuilder
, and have areclaimed
attribute, indicating the amount of space reclaimed (in bytes)
- Prune events are returned for
- Add
one-shot
stats option to not prime the stats moby/moby#40478 - Adding OS version info to the system info’s API (
/info
) moby/moby#38349 - Add DefaultAddressPools to docker info moby/moby#40714
- Add API support for PidsLimit on services moby/moby#39882
Builder
- buildkit,dockerfile: Support for
RUN --mount
options without needing to specify experimental dockerfile#syntax
directive. moby/buildkit#1717 - dockerfile:
ARG
command now supports defining multiple build args on the same line similarly toENV
moby/buildkit#1692 - dockerfile:
--chown
flag inADD
now allows parameter expansion moby/buildkit#1473 - buildkit: Fetching authorization tokens has been moved to client-side (if the client supports it). Passwords do not leak into the build daemon anymore and users can see from build output when credentials or tokens are accessed. moby/buildkit#1660
- buildkit: Connection errors while communicating with the registry for push and pull now trigger a retry moby/buildkit#1791
- buildkit: Git source now supports token authentication via build secrets moby/moby#41234docker/cli#2656moby/buildkit#1533
- buildkit: Building from git source now supports forwarding SSH socket for authentication moby/buildkit#1782
- buildkit: Avoid builds that generate excessive logs to cause a crash or slow down the build. Clipping is performed if needed. moby/buildkit#1754
- buildkit: Change default Seccomp profile to the one provided by Docker moby/buildkit#1807
- buildkit: Support for exposing SSH agent socket on Windows has been improved moby/buildkit#1695
- buildkit: Disable truncating by default when using --progress=plain moby/buildkit#1435
- buildkit: Allow better handling client sessions dropping while it is being shared by multiple builds moby/buildkit#1551
- buildkit: secrets: allow providing secrets with env moby/moby#41234docker/cli#2656moby/buildkit#1534
- Support
--secret id=foo,env=MY_ENV
as an alternative for storing a secret value to a file. --secret id=GIT_AUTH_TOKEN
will load env if it exists and the file does not.
- Support
- buildkit: Support for mirrors fallbacks, insecure TLS and custom TLS config moby/moby#40814
- buildkit: remotecache: Only visit each item once when walking results moby/moby#41234moby/buildkit#1577
- Improves performance and CPU use on bigger graphs
- buildkit: Check remote when local image platform doesn’t match moby/moby#40629
- buildkit: image export: Use correct media type when creating new layer blobs moby/moby#41234moby/buildkit#1541
- buildkit: progressui: fix logs time formatting moby/moby#41234docker/cli#2656moby/buildkit#1549
- buildkit: mitigate containerd issue on parallel push moby/moby#41234moby/buildkit#1548
- buildkit: inline cache: fix handling of duplicate blobs moby/moby#41234moby/buildkit#1568
- Fixes https://github.com/moby/buildkit/issues/1388 cache-from working unreliably
- Fixes https://github.com/moby/moby/issues/41219 Image built from cached layers is missing data
- Allow ssh:// for remote context URLs moby/moby#40179
- builder: remove legacy build’s session handling (was experimental) moby/moby#39983
Client
- Add swarm jobs support to CLI docker/cli#2262
- Add
-a/--all-tags
to docker push docker/cli#2220 - Add support for Kubernetes username/password auth docker/cli#2308
- Add
--pull=missing|always|never
torun
andcreate
commands docker/cli#1498 - Add
--env-file
flag todocker exec
for parsing environment variables from a file docker/cli#2602 - Add shorthand
-n
for--tail
option docker/cli#2646 - Add log-driver and options to service inspect “pretty” format docker/cli#1950
- docker run: specify cgroup namespace mode with
--cgroupns
docker/cli#2024 docker manifest rm
command to remove manifest list draft from local storage docker/cli#2449- Add “context” to “docker version” and “docker info” docker/cli#2500
- Propagate platform flag to container create API docker/cli#2551
- The
docker ps --format
flag now has a.State
placeholder to print the container’s state without additional details about uptime and health check docker/cli#2000 - Add support for docker-compose schema v3.9 docker/cli#2073
- Add support for docker push
--quiet
docker/cli#2197 - Hide flags that are not supported by BuildKit, if BuildKit is enabled docker/cli#2123
- Update flag description for
docker rm -v
to clarify the option only removes anonymous (unnamed) volumes docker/cli#2289 - Improve tasks printing for docker services docker/cli#2341
- docker info: list CLI plugins alphabetically docker/cli#2236
- Fix order of processing of
--label-add/--label-rm
,--container-label-add/--container-label-rm
, and--env-add/--env-rm
flags ondocker service update
to allow replacing existing values docker/cli#2668 - Fix
docker rm --force
returning a non-zero exit code if one or more containers did not exist docker/cli#2678 - Improve memory stats display by using
total_inactive_file
instead ofcache
docker/cli#2415 - Mitigate against YAML files that has excessive aliasing docker/cli#2117
- Allow using advanced syntax when setting a config or secret with only the source field docker/cli#2243
- Fix reading config files containing
username
andpassword
auth even ifauth
is empty docker/cli#2122 - docker cp: prevent NPE when failing to stat destination docker/cli#2221
- config: preserve ownership and permissions on configfile docker/cli#2228
Logging
- Support reading
docker logs
with all logging drivers (best effort) moby/moby#40543 - Add
splunk-index-acknowledgment
log option to work with Splunk HECs with index acknowledgment enabled moby/moby#39987 - Add partial metadata to journald logs moby/moby#41407
- Reduce allocations for logfile reader moby/moby#40796
- Fluentd: add fluentd-async, fluentd-request-ack, and deprecate fluentd-async-connect moby/moby#39086
Runtime
- Support cgroup2 moby/moby#40174moby/moby#40657moby/moby#40662
- cgroup2: use “systemd” cgroup driver by default when available moby/moby#40846
- new storage driver: fuse-overlayfs moby/moby#40483
- Update containerd binary to v1.4.3 moby/moby#41732
docker push
now defaults tolatest
tag instead of all tags moby/moby#40302- Added ability to change the number of reconnect attempts during connection loss while pulling an image by adding max-download-attempts to the config file moby/moby#39949
- Add support for containerd v2 shim by using the now default
io.containerd.runc.v2
runtime moby/moby#41182 - cgroup v1: change the default runtime to io.containerd.runc.v2. Requires containerd v1.3.0 or later. v1.3.5 or later is recommended moby/moby#41210
- Start containers in their own cgroup namespaces moby/moby#38377
- Enable DNS Lookups for CIFS Volumes moby/moby#39250
- Use MemAvailable instead of MemFree to estimate actual available memory moby/moby#39481
- The
--device
flag indocker run
will now be honored when the container is started in privileged mode moby/moby#40291 - Enforce reserved internal labels moby/moby#40394
- Raise minimum memory limit to 6M, to account for higher memory use by runtimes during container startup moby/moby#41168
- Add support for
CAP_PERFMON
,CAP_BPF
, andCAP_CHECKPOINT_RESTORE
on supported kernels moby/moby#41460 - vendor runc v1.0.0-rc92 moby/moby#41344moby/moby#41317
- info: add warnings about missing blkio cgroup support moby/moby#41083
- Accept platform spec on container create moby/moby#40725
- Fix handling of looking up user- and group-names with spaces moby/moby#41377
Networking
- Support host.docker.internal in dockerd on Linux moby/moby#40007
- Include IPv6 address of linked containers in /etc/hosts moby/moby#39837
--ip6tables
enables IPv6 iptables rules (only if experimental) moby/moby#41622- Add alias for hostname if hostname != container name moby/moby#39204
- Better selection of DNS server (with systemd) moby/moby#41022
- Add docker interfaces to firewalld docker zone moby/moby#41189moby/libnetwork#2548
- Fixes DNS issue on CentOS8 docker/for-linux#957
- Fixes Port Forwarding on RHEL 8 with Firewalld running with FirewallBackend=nftables moby/libnetwork#2496
- Fix an issue reporting ‘failed to get network during CreateEndpoint’ moby/moby#41189moby/libnetwork#2554
- Log error instead of disabling IPv6 router advertisement failed moby/moby#41189moby/libnetwork#2563
- No longer ignore
--default-address-pool
option in certain cases moby/moby#40711 - Produce an error with invalid address pool moby/moby#40808moby/libnetwork#2538
- Fix
DOCKER-USER
chain not created when IPTableEnable=false moby/moby#40808moby/libnetwork#2471 - Fix panic on startup in systemd environments moby/moby#40808moby/libnetwork#2544
- Fix issue preventing containers to communicate over macvlan internal network moby/moby#40596moby/libnetwork#2407
- Fix InhibitIPv4 nil panic moby/moby#40596
- Fix VFP leak in Windows overlay network deletion moby/moby#40596moby/libnetwork#2524
Packaging
- docker.service: Add multi-user.target to After= in unit file moby/moby#41297
- docker.service: Allow socket activation moby/moby#37470
- seccomp: Remove dependency in dockerd on libseccomp moby/moby#41395
Rootless
- rootless: graduate from experimental moby/moby#40759
- Add dockerd-rootless-setuptool.sh moby/moby#40950
- Support
--exec-opt native.cgroupdriver=systemd
moby/moby#40486
Security
Ubuntu Docker Group
- Fix CVE-2019-14271 loading of nsswitch based config inside chroot under Glibc moby/moby#39612
- seccomp: Whitelist
clock_adjtime
.CAP_SYS_TIME
is still required for time adjustment moby/moby#40929 - seccomp: Add openat2 and faccessat2 to default seccomp profile moby/moby#41353
- seccomp: allow ‘rseq’ syscall in default seccomp profile moby/moby#41158
- seccomp: allow syscall membarrier moby/moby#40731
- seccomp: whitelist io-uring related system calls moby/moby#39415
- Add default sysctls to allow ping sockets and privileged ports with no capabilities moby/moby#41030
- Fix seccomp profile for clone syscall moby/moby#39308
Swarm
Ubuntu Docker Group Id
- Add support for swarm jobs moby/moby#40307
- Add capabilities support to stack/service commands docker/cli#2687docker/cli#2709moby/moby#39173moby/moby#41249
- Add support for sending down service Running and Desired task counts moby/moby#39231
- service: support
--mount type=bind,bind-nonrecursive
moby/moby#38788 - Support ulimits on Swarm services. moby/moby#41284docker/cli#2712
- Fixed an issue where service logs could leak goroutines on the worker moby/moby#40426