...
RUN mkdir -p /usr/src/ether \
&& curl -SL http://vacuum.com/huge.tar.xz \
| tar -xJC /usr/src/ether \
&& make -C /usr/src/ether all
6.Chain commands together to reduce the number of layers
A new container layer is created for every new instruction in the Dockerfile. Commands that are chained together become part of the same image layer.
To provide a good understanding of the content of each layer, group related operations together so that they become part of a single layer.
Take for example:
RUN dnf install -y --setopt=tsflags=nodocs \
httpd vim && \
systemctl enable httpd && \
dnf clean all
Each command associated with the installation and configuration of httpd is grouped and creates a single layer. Grouping operations this way reduces the number of layers and contributes to the legibility of the instructions.