Known issues

When building cOS or a cOS derivative, you could face different issues, this section provides a description of the most known ones, and way to workaround them.

Building SELinux fails

cOS by default has SELinux enabled in permissive mode. If you are building parts of cOS or cOS itself from scratch, you might encounter issues while building the SELinux module, like so:

Step 12/13 : RUN checkmodule -M -m -o cOS.mod cOS.te && semodule_package -o cOS.pp -m cOS.mod
  ---> Using cache
 ---> 1be520969ead
Step 13/13 : RUN semodule -i cOS.pp
  ---> Running in c5bfa5ae92e2
 libsemanage.semanage_commit_sandbox: Error while renaming /var/lib/selinux/targeted/active to /var/lib/selinux/targeted/previous. (Invalid cross-device link).
semodule:  Failed!
 The command '/bin/sh -c semodule -i cOS.pp' returned a non-zero code: 1
 Error: while resolving join images: failed building join image: Failed compiling system/selinux-policies-0.0.6+3: failed building package image: Could not push image: raccos/sampleos:ffc8618ecbfbffc11cc3bca301cc49867eb7dccb623f951dd92caa10ced29b68 selinux-policies-system-0.0.6+3.dockerfile: Could not build image: raccos/sampleos:ffc8618ecbfbffc11cc3bca301cc49867eb7dccb623f951dd92caa10ced29b68 selinux-policies-system-0.0.6+3.dockerfile: Failed running command: : exit status 1
 Bailing out
make: *** [Makefile:45: build] Error 1

The issue is possibly caused by https://github.com/docker/for-linux/issues/480 . A workaround is to switch the storage driver of Docker. Check if your storage driver is overlay2, and switch it to devicemapper

Multi-stage copy build fails

While processing images with several stage copy, you could face the following:

 🐋  Building image raccos/sampleos:cc0aee4ff6c194f920a945c45ebcb487c3e22c5ab40e2634ea70c064dfab206d done
 📦  8/8 system/cos-0.5.3+1 ⤑ 🔨  build system/selinux-policies-0.0.6+3 ✅  Done
 🚀  All dependencies are satisfied, building package requested by the user system/cos-0.5.3+1
 📦  system/cos-0.5.3+1  Using image:  raccos/sampleos:cc0aee4ff6c194f920a945c45ebcb487c3e22c5ab40e2634ea70c064dfab206d
 📦  system/cos-0.5.3+1 🐋  Generating 'builder' image from raccos/sampleos:cc0aee4ff6c194f920a945c45ebcb487c3e22c5ab40e2634ea70c064dfab206d as raccos/sampleos:builder-8533d659df2505a518860bd010b7a8ed with prelude steps
🚧  warning Failed to download 'raccos/sampleos:builder-8533d659df2505a518860bd010b7a8ed'. Will keep going and build the image unless you use --fatal
🚧  warning Failed pulling image: Error response from daemon: manifest for raccos/sampleos:builder-8533d659df2505a518860bd010b7a8ed not found: manifest unknown: manifest unknown
: exit status 1
 🐋  Building image raccos/sampleos:builder-8533d659df2505a518860bd010b7a8ed
 Sending build context to Docker daemon  9.728kB
 Step 1/10 : FROM raccos/sampleos:cc0aee4ff6c194f920a945c45ebcb487c3e22c5ab40e2634ea70c064dfab206d
  ---> f1122e79b17e
Step 2/10 : COPY . /luetbuild
  ---> 4ff3e202951b
 Step 3/10 : WORKDIR /luetbuild
  ---> Running in 7ec571b96c6f
 Removing intermediate container 7ec571b96c6f
  ---> 9e05366f830a
Step 4/10 : ENV PACKAGE_NAME=cos
  ---> Running in 30297dbd21a3
 Removing intermediate container 30297dbd21a3
  ---> 4c4838b629f4
 Step 5/10 : ENV PACKAGE_VERSION=0.5.3+1
  ---> Running in 36361b617252
 Removing intermediate container 36361b617252
  ---> 6ac0d3a2ff9a
Step 6/10 : ENV PACKAGE_CATEGORY=system
  ---> Running in f20c2cf3cf34
 Removing intermediate container f20c2cf3cf34
  ---> a902ff95d273
 Step 7/10 : COPY --from=quay.io/costoolkit/build-cache:f3a333095d9915dc17d7f0f5629a638a7571a01dcf84886b48c7b2e5289a668a /usr/bin/yip /usr/bin/yip
  ---> 42fa00d9c990
 Step 8/10 : COPY --from=quay.io/costoolkit/build-cache:e3bbe48c6d57b93599e592c5540ee4ca7916158461773916ce71ef72f30abdd1 /usr/bin/luet /usr/bin/luet
 e3bbe48c6d57b93599e592c5540ee4ca7916158461773916ce71ef72f30abdd1: Pulling from costoolkit/build-cache
 3599716b36e7:  Already exists
 24a39c0e5d06: Already exists
 4f4fb700ef54: Already exists
 4f4fb700ef54: Already exists
 4f4fb700ef54: Already exists
 378615c429f5: Already exists
 c28da22d3dfd:  Already exists
 ddb4dd5c81b0: Already exists
 92db41c0c9ab: Already exists
 4f4fb700ef54: Already exists
 6e0ca71a6514: Already exists
 47debb886c7d: Already exists
 4f4fb700ef54: Already exists
 4f4fb700ef54: Already exists
 4f4fb700ef54: Already exists
 d0c9d0f8ddb6: Already exists
 e5a48f1f72ad:  Pulling fs layer
 4f4fb700ef54:  Pulling fs layer
 7d603b2e4a37:  Pulling fs layer
 64c4d787e344:  Pulling fs layer
 f8835d2e60d1:  Pulling fs layer
 64c4d787e344:  Waiting
 f8835d2e60d1:  Waiting
 e5a48f1f72ad:  Download complete
 e5a48f1f72ad:  Pull complete
 4f4fb700ef54:  Verifying Checksum
 4f4fb700ef54:  Download complete
 4f4fb700ef54:  Pull complete
 7d603b2e4a37: Verifying Checksum
7d603b2e4a37: Download complete
 64c4d787e344: Verifying Checksum
64c4d787e344: Download complete
 7d603b2e4a37: Pull complete
 64c4d787e344: Pull complete
 f8835d2e60d1:  Verifying Checksum
 f8835d2e60d1:  Download complete
 f8835d2e60d1: Pull complete
 Digest: sha256:9b58bed47ff53f2d6cc517a21449cae686db387d171099a4a3145c8a47e6a1e0
 Status: Downloaded newer image for quay.io/costoolkit/build-cache:e3bbe48c6d57b93599e592c5540ee4ca7916158461773916ce71ef72f30abdd1
 failed to export image: failed to create image: failed to get layer sha256:118537d8997a08750ab1ac3d8e8575e40fe60e8337e02633b0d8a1287117fe78: layer does not exist
 Error: while resolving join images: failed building join image: failed building package image: Could not push image: raccos/sampleos:cc0aee4ff6c194f920a945c45ebcb487c3e22c5ab40e2634ea70c064dfab206d cos-system-0.5.3+1-builder.dockerfile: Could not build image: raccos/sampleos:cc0aee4ff6c194f920a945c45ebcb487c3e22c5ab40e2634ea70c064dfab206d cos-system-0.5.3+1-builder.dockerfile: Failed running command: : exit status 1
 Bailing out
make: *** [Makefile:45: build] Error 1

There is a issue open upstream about it. A workaround is to enable Docker buildkit with DOCKER_BUILDKIT=1.