Operations

What is Custom ISO?

Definition

Custom ISO support lets you upload an installer image and boot the instance from it, rather than choosing from a fixed template list. It is the escape hatch that makes a VPS genuinely general-purpose: BSDs, hardened images, appliance operating systems and anything you built yourself.

Why Custom ISO matters

It is the escape hatch that makes a VPS genuinely general-purpose: BSDs, hardened images, appliance operating systems and anything you built yourself.

Custom ISO in practice

When you boot a Custom ISO, you are trading the provider's tested images for your own. You would watch the out-of-band VNC console during install, because your kernel has to bring up the virtio drivers itself. You would change your boot order so the installer starts before the disk. Get the image's format wrong and the console sits at a blank prompt; you then re-upload and start again. That costs you time, not money — the upload is included.

What people get wrong about Custom ISO

People assume a Custom ISO gives you a bootable system. It does not: it is an installer image. The common error is uploading a live environment, booting it, and treating that as your server. When you reboot, you are back at the installer prompt. The correction: install to the disk from the ISO, then boot the disk for normal operation.

Custom ISO — common questions

Can I run a Custom ISO permanently?

Technically yes, but it is an installer image, not a running system. Most installers will not persist state. Boot the ISO, install to the virtual disk, then boot from that disk. If you want a live environment permanently, build a custom disk image instead.

Does uploading a Custom ISO cost extra?

No. Custom ISO upload is included at every tier, in every region. You pay nothing for the upload or the boot. Your only costs are the instance itself and any optional extras like additional IPv4 addresses or backups.

More from operations

SLA
An SLA is a contractual commitment to a service level, usually availability, with defined compensation when it is missed.
Out-of-band console
An out-of-band console attaches to a virtual machine's display and keyboard independently of its network connection.
Terraform
Terraform declares infrastructure in configuration files and reconciles the real environment against them.
Seedbox
A seedbox is a server dedicated to downloading and seeding torrents at high speed, typically with large storage and a fast uplink.
Control panel
A control panel is a web interface for administering servers, websites, mail and databases — cPanel, DirectAdmin, CyberPanel and similar.
Provisioning
Provisioning is the process of creating, configuring and delivering a server so that it is ready to use.