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Update best-practices.md #21045

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20 changes: 10 additions & 10 deletions content/manuals/build/building/best-practices.md
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Original file line number Diff line number Diff line change
Expand Up @@ -98,7 +98,7 @@ download of base images and dependencies.
```dockerfile
# syntax=docker/dockerfile:1
FROM ubuntu:24.04
RUN apt-get -y update && apt-get install -y python
RUN apt-get -y update && apt-get install -y --no-install-recommends python3
```

Also consider [pinning base image versions](#pin-base-image-versions).
Expand Down Expand Up @@ -165,7 +165,7 @@ review. Adding a space before a backslash (`\`) helps as well.
Here’s an example from the [buildpack-deps image](https://github.com/docker-library/buildpack-deps):

```dockerfile
RUN apt-get update && apt-get install -y \
RUN apt-get update && apt-get install -y --no-install-recommends \
bzr \
cvs \
git \
Expand Down Expand Up @@ -324,7 +324,7 @@ For example, you can chain commands with the `&&` operator, and use
use escape characters to break long commands into multiple lines.

```dockerfile
RUN apt-get update && apt-get install -y \
RUN apt-get update && apt-get install -y --no-install-recommends \
package-bar \
package-baz \
package-foo
Expand All @@ -339,7 +339,7 @@ with a pipeline operator:
```dockerfile
RUN <<EOF
apt-get update
apt-get install -y \
apt-get install -y --no-install-recommends \
package-bar \
package-baz \
package-foo
Expand All @@ -358,7 +358,7 @@ Always combine `RUN apt-get update` with `apt-get install` in the same `RUN`
statement. For example:

```dockerfile
RUN apt-get update && apt-get install -y \
RUN apt-get update && apt-get install -y --no-install-recommends \
package-bar \
package-baz \
package-foo
Expand All @@ -372,7 +372,7 @@ subsequent `apt-get install` instructions to fail. For example, this issue will

FROM ubuntu:22.04
RUN apt-get update
RUN apt-get install -y curl
RUN apt-get install -y --no-install-recommends curl
```

After building the image, all layers are in the Docker cache. Suppose you later
Expand All @@ -383,7 +383,7 @@ modify `apt-get install` by adding an extra package as shown in the following Do

FROM ubuntu:22.04
RUN apt-get update
RUN apt-get install -y curl nginx
RUN apt-get install -y --no-install-recommends curl nginx
```

Docker sees the initial and modified instructions as identical and reuses the
Expand All @@ -392,14 +392,14 @@ because the build uses the cached version. Because the `apt-get update` isn't
run, your build can potentially get an outdated version of the `curl` and
`nginx` packages.

Using `RUN apt-get update && apt-get install -y` ensures your Dockerfile
Using `RUN apt-get update && apt-get install -y --no-install-recommends` ensures your Dockerfile
installs the latest package versions with no further coding or manual
intervention. This technique is known as cache busting. You can also achieve
cache busting by specifying a package version. This is known as version pinning.
For example:

```dockerfile
RUN apt-get update && apt-get install -y \
RUN apt-get update && apt-get install -y --no-install-recommends \
package-bar \
package-baz \
package-foo=1.3.*
Expand All @@ -413,7 +413,7 @@ Below is a well-formed `RUN` instruction that demonstrates all the `apt-get`
recommendations.

```dockerfile
RUN apt-get update && apt-get install -y \
RUN apt-get update && apt-get install -y --no-install-recommends \
aufs-tools \
automake \
build-essential \
Expand Down
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