معمل 18.1: Build an image-mode web server, update it and roll back

هذا الجزء لم يُترجم بعد. أنت ترى النص الإنجليزي.

الهدف

Build a bootable container image with Apache, turn it into a KVM disk, boot a VM from it, then ship version 2 as an update — and roll it back.

قبل أن تبدأ

A RHEL 10 machine with KVM (virt-install) and at least 20 GiB free disk, registered, with access to registry.redhat.io (podman login registry.redhat.io).
A registry the VM can pull from. The easiest is a free account on quay.io (make the repository public), or a local registry on server1.
sudo dnf install -y container-tools virt-install.
In the tasks, replace quay.io/YOURNAME with your own registry path.

المهام

Write a Containerfile that starts from registry.redhat.io/rhel10/rhel-bootc:10.0, installs httpd, enables it, opens nothing else, and serves a page version 1 from /usr/share/web/html.
Build the image as quay.io/YOURNAME/web-bootc:1.0, test that httpd is in it, and push it. Also tag and push it as :prod.
Make a qcow2 disk with bootc-image-builder. Add a user admin in wheel with your SSH key.
Boot a VM bootc1 from the disk. Log in as admin and check the image with bootc status. Make sure the VM follows the tag :prod.
Change the page to version 2, build :2.0, and push it as :prod. Update bootc1 and reboot it.
Roll bootc1 back to version 1 and reboot again.

تحقّق من عملك

$ssh admin@BOOTC1 'sudo bootc status'
$curl -s http://BOOTC1/
$ssh admin@BOOTC1 'rpm -q httpd; systemctl is-enabled httpd'

After task 5, curl prints version 2 and bootc status shows a rollback image.
After task 6, curl prints version 1.

تلميحات

اعرض التلميحات

/var is not updated by new images. Put the web page in /usr/share/web/html and point Apache there with a small config file in /etc/httpd/conf.d/.
bootc-image-builder runs as root and reads root's container storage: sudo podman pull the image first.
A VM made from the :1.0 disk follows :1.0. bootc switch quay.io/YOURNAME/web-bootc:prod makes it follow :prod.
On the KVM host, virsh domifaddr bootc1 shows the address of the VM. The libvirt network lets the host reach port 80 of the VM.

الحل

اعرض الحل

The build folder.

$mkdir -p ~/web-bootc/html && cd ~/web-bootc
$echo "version 1" > html/index.html
$printf 'DocumentRoot "/usr/share/web/html"\n<Directory "/usr/share/web/html">\n    Require all granted\n</Directory>\n' > web.conf
$cat Containerfile
FROM registry.redhat.io/rhel10/rhel-bootc:10.0
RUN dnf -y install httpd && dnf clean all
COPY web.conf /etc/httpd/conf.d/web.conf
COPY html/ /usr/share/web/html/
RUN systemctl enable httpd

Build, test, push.

$podman login registry.redhat.io
$podman login quay.io
$podman build -t quay.io/YOURNAME/web-bootc:1.0 .
$podman run --rm quay.io/YOURNAME/web-bootc:1.0 rpm -q httpd
$podman push quay.io/YOURNAME/web-bootc:1.0
$podman tag quay.io/YOURNAME/web-bootc:1.0 quay.io/YOURNAME/web-bootc:prod
$podman push quay.io/YOURNAME/web-bootc:prod

The disk image (as root).

$cat config.toml
[[customizations.user]]
name = "admin"
key = "ssh-ed25519 AAAA...your-key"
groups = ["wheel"]
$sudo podman pull quay.io/YOURNAME/web-bootc:prod
$mkdir -p output
$sudo podman run --rm -it --privileged --pull=newer --security-opt label=type:unconfined_t -v ./config.toml:/config.toml:ro -v ./output:/output -v /var/lib/containers/storage:/var/lib/containers/storage registry.redhat.io/rhel10/bootc-image-builder:latest --type qcow2 quay.io/YOURNAME/web-bootc:prod

Boot the VM and check it.

$sudo cp output/qcow2/disk.qcow2 /var/lib/libvirt/images/bootc1.qcow2
$sudo virt-install --name bootc1 --memory 2048 --vcpus 2 --import --disk /var/lib/libvirt/images/bootc1.qcow2 --os-variant rhel10.0 --graphics none --noautoconsole
$sudo virsh domifaddr bootc1
$ssh admin@BOOTC1 'sudo bootc status'
$curl -s http://BOOTC1/

Version 2 as an update.

$echo "version 2" > html/index.html
$podman build -t quay.io/YOURNAME/web-bootc:2.0 .
$podman push quay.io/YOURNAME/web-bootc:2.0
$podman tag quay.io/YOURNAME/web-bootc:2.0 quay.io/YOURNAME/web-bootc:prod
$podman push quay.io/YOURNAME/web-bootc:prod
$ssh admin@BOOTC1 'sudo bootc upgrade --apply'
$curl -s http://BOOTC1/

Roll back.

$ssh admin@BOOTC1 'sudo bootc rollback && sudo systemctl reboot'
$curl -s http://BOOTC1/

ملاحظاتي

لا توجد ملاحظات بعد.

Build an image-mode web server, update it and roll back