Operating systems

Your catalogue is the list of operating systems you offer. Each entry is linked to something concrete per integration: a template on your hypervisor, or a network installation profile.

A template is a machine on your own hypervisor that Provibr clones. You can build one yourself, or let the platform build one for you: the catalogue page hands out a command you run on your own node, which fetches a cloud image, prepares it and turns it into a template.

Preparing an image is a fixed sequence: copy it, read its architecture, grow the filesystem, update the package index, install what a cloud machine needs, configure it, verify that root login over SSH works, check that host keys will be regenerated, wipe machine-specific identity, and take a checksum.

The agent can serve a network boot itself: it answers the boot request, hands out a boot loader, serves the kernel and the installer, and provides the answer file that makes the installation unattended. Nothing has to run on your network beforehand.

A profile is one installation described end to end. There is a set your provider maintains that you can clone, and there are your own.

• Distribution, release and architecture, and the answer format that belongs to it.
• Where the installation medium comes from: served by the agent, which works without a route to the internet, or fetched from a mirror, which needs one.
• Network: from the boot server, or a fixed address taken from your own address management.
• Disk layout, SSH policy, extra packages, locale, keyboard and time zone.
• Commands to run after the installation, either inside the installer or inside the installed system.

Network installation is switched on per agent, on its own tab. You choose which network interface it listens on, and the interface choice is enforced by the kernel rather than by the program.

By default the agent answers alongside the address server you already have, adding only what a network boot needs. It can also hand out addresses itself, but that is presented as a test facility: it needs one specific interface and one address block, it asks for confirmation, and it switches itself off again after a day.

You start it from the server's settings tab. Provibr checks everything it can check before the button does anything: the agent supports it, the integration is set to install over the network, the service is on, the machine has known hardware addresses, and the profile has everything it needs.

The order matters and is deliberate. Your agent is told to listen first, and only once it confirms is the machine powered on. The other way round, the machine would boot before anything was listening, get no answer and quietly fall back to its disk.

The root password and the SSH keys go into the answer file the installer reads. The rendered file is never stored, and the audit trail records only that those fields were filled in.

The agent records what it saw, stage by stage: whether the service was listening, whether a boot request arrived, whether the boot loader was fetched, whether the kernel started, whether the installer called back. Reaching a stage proves the ones before it, so the last stage reached is the whole diagnosis.

• No request at all: the machine never asked. Check that it boots from the network and that the agent is on the right segment.
• A request arrived but did not match: the hardware address in the request is not the one recorded on the server.
• The answer was sent but the boot loader was never fetched, usually because of another boot server on the same segment, or a firmware that cannot reach the agent's port.
• The boot loader ran but the kernel, the initial ramdisk or the answer file failed.
• The installer started and never reported back. From here on it is the installation itself, and its own log is the place to look.

Whatever the agent has to fetch for an installation is kept on its disk, addressed by checksum and verified by signature. The second machine you install therefore does not download it again.

From the agent's cache tab you can inspect what is there, fetch something in advance, verify it, delete an entry and empty the whole cache. Viewing and changing are separate permissions.