Got it, since Docker CE dropped support for CentOS 6 entirely, you've got a few solid alternatives to build and run a CentOS 6.9 32-bit container image. Let's break them down:

Option 1: Use an Older Docker Version (1.13.x or Earlier) #

Docker versions up to 1.13.x still supported CentOS 6. Here's how to set this up:

1. First, fix your CentOS 6 repos (since official repos are archived):
   Edit /etc/yum.repos.d/CentOS-Base.repo to point to the CentOS 6 vault:

   [base]
   name=CentOS-6 - Base
   baseurl=http://vault.centos.org/6.9/os/i386/
   gpgcheck=1
   gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
   
   [updates]
   name=CentOS-6 - Updates
   baseurl=http://vault.centos.org/6.9/updates/i386/
   gpgcheck=1
   gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
   
   [extras]
   name=CentOS-6 - Extras
   baseurl=http://vault.centos.org/6.9/extras/i386/
   gpgcheck=1
   gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
   

2. Install dependencies and older Docker:

   yum install -y yum-utils device-mapper-persistent-data lvm2
   yum-config-manager --add-repo https://get.docker.com/rpm/1.13.0/centos-6/RPMS/i386/
   yum install docker-engine-1.13.1-1.el6.i686
   

3. Start Docker and build your image:

   • Start the service: service docker start
   • You can now use a Dockerfile based on the official (archived) CentOS 6 32-bit image, or build your own. For example, a minimal Dockerfile:

     FROM centos:6.9-i386
     RUN yum update -y && yum install -y your-packages-here
     CMD ["/bin/bash"]
     

   • Build with: docker build -t centos69-32bit .

Option 2: Use LXC (Linux Containers) #

LXC has better support for older distributions like CentOS 6, and it's included in the CentOS 6 repos:

1. Install LXC and templates:

   yum install -y lxc lxc-templates
   

2. Create a CentOS 6.9 32-bit container:

   lxc-create -n centos6-32 -t centos -- --release 6 --arch i386
   

   This will pull the necessary packages and set up a full CentOS 6.9 32-bit root filesystem.

3. Customize and export the image:

   • Start the container: lxc-start -n centos6-32
   • Attach to it to install software/configure: lxc-attach -n centos6-32
   • When done, stop the container: lxc-stop -n centos6-32
   • Export the rootfs as a tarball (your reusable image):

     tar -czf centos69-32bit-lxc.tar.gz /var/lib/lxc/centos6-32/rootfs/
     

   • To reuse this image elsewhere, just unpack the tarball into a new LXC container's rootfs directory.

Option 3: Manually Build a RootFS and Import to a Container Tool #

If you want full control, build a CentOS 6.9 32-bit root filesystem from scratch, then import it into Docker (older version) or LXC:

1. Build the rootfs:

   yum install -y yum-utils
   mkdir /tmp/centos6-rootfs
   yum --installroot=/tmp/centos6-rootfs --releasever=6 --arch=i386 groupinstall "Base"
   yum --installroot=/tmp/centos6-rootfs clean all
   

2. Import to older Docker:

   tar -C /tmp/centos6-rootfs -c . | docker import - centos69-32bit:custom
   

3. Or use with LXC:

   • Create a new empty LXC container: lxc-create -n centos6-custom -t empty
   • Replace its rootfs: rm -rf /var/lib/lxc/centos6-custom/rootfs/* && tar -xf centos69-32bit.tar.gz -C /var/lib/lxc/centos6-custom/rootfs/
   • Start it: lxc-start -n centos6-custom

Key Notes #

• CentOS 6 is end-of-life, so always use the vault repos to avoid broken links.
• Older Docker versions won't get security updates, so only use this in isolated environments if possible.
• LXC is a lighter alternative without Docker's overhead, which might be better for legacy systems.

内容的提问来源于stack exchange，提问作者vico