Feature to make variations of init container Dockerfiles for other platforms like OCP

[mregmi]

Currently there is only one variation of Dockerfile for initcontainers. But they differ a bit between vanilla Kubernetes and OpenShift. So we currently modify the Dockerfile to customize for OpenShift. It would be nice if we can do make dockerfile to create a separate Dockerfiles for OCP (when run with ENV variable). Some differences are below.

• we use different base image (RedHat UBI)
• We cannot use the currently used toybox as it modifies base image's /bin
• We need some custom commands to install packages as UBI image is small and does not contain everything we need.

[mythi]

We need some custom commands to install packages as UBI image is small and does not contain everything we need.

what are the binaries missing from UBI that the initcontainers need?

[mregmi]

it is grep, findutils and pciutils. but they should be in toybox.

[mythi]

it is grep, findutils and pciutils. but they should be in toybox.

yup,

 grep ^CONFIG build/docker/toybox-config-ubi9-micro 
CONFIG_TOYBOX_FORK=y
CONFIG_GREP=y
CONFIG_EGREP=y
CONFIG_FGREP=y
CONFIG_LSPCI=y
CONFIG_TOYBOX=y
CONFIG_TOYBOX_LSM_NONE=y
CONFIG_TOYBOX_UID_SYS=100
CONFIG_TOYBOX_UID_USR=500

[mythi]

it is grep, findutils and pciutils

find is not covered but there it is needed?

[mregmi]

Actually find is not needed for this. it was for driver image so not needed here.

[mythi]

Fixed by #1615