Qemu only : linux/arm/v7 'Command 'install' is not valid, try 'pecl help'

[ohnotnow]

Resubmitting from docker-library/php#893 .

Slightly odd issue - if I try and build a multiarch image and use a pecl install redis as part of it - then it fails on the linux/arm/v7 build. Example Dockerfile :

FROM php:7.3-apache
RUN pecl install redis && docker-php-ext-enable redis

Running :

docker buildx build --pull --load --no-cache --platform linux/arm/v7 -t test-pecl -f Dockerfile .

Fails with

 => ERROR [2/2] RUN pecl install redis && docker-php-ext-enable redis      1.3s
------                                                                          
 > [2/2] RUN pecl install redis && docker-php-ext-enable redis:                 
#5 0.583 Command 'install' is not valid, try 'pecl help' 

Running :

docker buildx build --pull --load --no-cache --platform linux/amd64 -t test-pecl -f Dockerfile .

Works fine. The docker version in front of me is Docker version 19.03.2, build 6a30dfc. Let me know if there's any more info I can supply or something to dig into :-)

Oh - and running the php:7.3 image on an actual ARM machine also runs pecl install redis a-ok as noted on the original issue linked above.

[StefanScherer]

Triaging this problem, I could reproduce the problem in

• Docker Desktop 2.1.0.2 (Docker engine 19.03.2) on Mac (kernel 4.9.184-linuxkit)
• a boot2docker 18.09.9 docker-machine in VirtualBox on the same Mac (kernel 4.19)
• a VMware Fusion Vagrant ubuntu box (kernel 4.15.0)

Interesting, I could run the build on CircleCI (docker 17.09.0, kernel 4.15.0) https://circleci.com/gh/StefanScherer/circle2test/81?pipelines-ui-opt-out in a quick-and-dirty test environment.

In all non-DockerDesktop environments I used this image to register QEMU

docker run --rm --privileged hypriot/qemu-register

and this slightly adjusted Dockerfile to explicitly pull the ARM image for a "normal" docker build -t phptest ..

FROM arm32v7/php:7.3-apache
RUN pecl install redis && docker-php-ext-enable redis

TL;DR It doesn't work on my MacBook, but it works on CircleCI. Different host CPU? 🤔

[JnMik]

Same issue here running

yes | pecl install apcu

in this docker file

FROM biarms/qemu-bin as qemu-bin-ref
FROM arm32v7/php:7.3-fpm
COPY --from=qemu-bin-ref /usr/bin/qemu-arm-static /usr/bin/qemu-arm-static
RUN yes | pecl install apcu

Will fail in the build phase with the error mentioned above

Edit: Mine fails on gitlab pipeline running in docker:19.03.1-dind I believe

[JnMik]

Anyone found a workaround ?