This repository contains the specfile and config files to build kernel-ml kernels that include AUFS for use with Docker. The Docker spec files that were part of the original repo are no longer included.

This has been tested on the following distributions:

• CentOS 6
• CentOS 7
• Red Hat Enterprise Linux 6
• Red Hat Enterprise Linux 7
• Red Hat Enterprise Linux 8 (see note below, currently in beta)

Other RHEL-derivatives should also work, but have not been tested.

There are two methods for getting prebuilt packages:

The first is to download them directly from the Spaceduck.org Yum repo. Install the .repo file into /etc/yum.repos.d to get updates automatically.

The second is to install the packages from Fedora Copr:

• .repo file for EL6
• .repo file for EL7
• .repo file for EL8

The Copr repo will only ever contain the most recently-built packages, where the spaceduck.org one should include historical RPMs as well. Please keep in mind that new packages are built as time allows, and that updates to this repo will often appear before the packages are built.

If you want these packages to be your default kernel in GRUB: edit /etc/sysconfig/kernel, and change DEFAULTKERNEL to DEFAULTKERNEL=kernel-ml-aufs.

Before building the packages, be sure to install the fedora-packager package, and add yourself to the mock group. If you're on Fedora, fedora-packager will be available from the base repos. EL users will need to install from EPEL.

Be aware that building the kernel can take a long time (at least half an hour, up to several hours if you're building on an older machine).

Run the build_ml_kernel.sh script, and either answer all three questions, or provide them as command-line parameters:

$ ./build_ml_kernel.sh
What kernel version do you want to build? (major version only)
3.19
What architecture do you want to build for? (i686, i686-NONPAE, x86_64)
x86_64
What version of CentOS/RHEL do you want to build for? (6 or 7)
7

or

$ ./build_ml_kernel.sh -v=3.19 -a=x86_64 -e=7

This will build your packages automatically. Logs for the build can be found in two places:

• $(REPO_LOCATION)/build/logs has the output from each command in separate log files.
• $(REPO_LOCATION)/build/output contains the mock logs so you can see where the build went wrong (if it went wrong at all).

If all goes well, your new RPMs will be moved to ~/RPMs. The build directory will remain behind for analysis.

If you'd rather run through the steps manually, you can do so with the instructions below. Be sure to change epel-6-x86_64 to epel-7-x86_64 and the filename for the source RPM if you're building for EL7.

Linux 4.x will use the AUFS 4.x tree in its packages. Linux 3.x will use AUFS 3.x.

In the example below, we're building kernel-ml 3.19.0 with the latest commit out of the AUFS tree (f60288dc0e0aab77ca545f42d785ec280f4700b9) at the time of writing. When you build your kernel versions, be sure to update this step to the latest commit.

spectool -g -C kernel-ml-aufs kernel-ml-aufs/kernel-ml-aufs-3.19.spec
git clone git://git.code.sf.net/p/aufs/aufs3-standalone -b aufs3.19
pushd aufs3-standalone
git archive f60288dc0e0aab77ca545f42d785ec280f4700b9 > ../kernel-ml-aufs/aufs3-standalone.tar
popd
mock -r epel-6-x86_64 --buildsrpm --spec kernel-ml-aufs/kernel-ml-aufs-3.19.spec --sources kernel-ml-aufs --resultdir output
mock -r epel-6-x86_64 --rebuild --resultdir output output/kernel-ml-aufs-3.19.0-1.el6.src.rpm

The resulting RPMs will be placed in a directory named output.

Once your packages are built, you can install them with yum. cd to the appropriate directory, and run:

yum localinstall --nogpgcheck kernel-ml-aufs-3.19.0-1.el6.x86_64.rpm

In order to use docker on EL6, you'll need to install it out of EPEL:

yum install docker-io

For EL7, Docker packages are in the main repos:

yum install docker

Reboot and choose the AUFS kernel from your GRUB menu (or edit GRUB to change your default kernel).

If everything is working as expected, you should see that AUFS is your storage driver when you run docker info:

[bnied@buildbox ~]$ sudo docker info
Containers: 0
Images: 0
Storage Driver: aufs
Root Dir: /var/lib/docker/aufs
Backing Filesystem: xfs
Dirs: 0
Dirperm1 Supported: true
Execution Driver: native-0.2
Kernel Version: 4.0.2-1.el7.centos.x86_64
Operating System: CentOS Linux 7 (Core)
CPUs: 2
Total Memory: 1.938 GiB
Name: buildbox.local
ID: BZQL:SPMI:Y23R:KBPK:SHR2:UTIN:Q2SS:N6SE:3DL2:PNKK:YP5D:OANX
WARNING: No swap limit support

If you're still seeing devicemapper as your storage backend, you'll need to change Docker's configuration to use AUFS. Open /etc/sysconfig/docker, and change line 4 from:

OPTIONS='--selinux-enabled'

to:

OPTIONS='--selinux-enabled --storage-driver=aufs'

Restart the Docker service, and it should switch to the correct backend.