Glossary
A plain-language reference for the terms you'll meet across the documentation. Look here whenever something is unfamiliar.
A–F
Application Credential
A set of credentials (ID + secret) used to authenticate against the OpenStack API, typically for the command-line client or automation. Safer than reusing your Horizon password.
Availability Zone
A physically isolated section within a region's data centre. Each region has three AZs (e.g. ch-zh1-az1, ch-zh1-az2, ch-zh1-az3). AZs within a region are coupled via VXLAN (Region 1) or GENEVE (Region 2) — private L2 networks stretch across all AZs. A VM cannot be moved between AZs after deployment. See Regions and Availability Zones.
Backup Management
The feature in the Cloud Services Portal for scheduling and restoring backups of your VMs and volumes.
Cloud Services Portal
The central web UI for managing projects, clients, users, storage, backups, quotas, and usage. Sits on top of OpenStack.
Client
The top-level administrative unit in the Cloud Services Portal. Groups users and billing and contains one or more projects.
clouds.yaml
A YAML configuration file that stores OpenStack connection details (auth URL, credentials, region). The OpenStack CLI and automation tools read it to authenticate without interactive login. Placed at ~/.config/openstack/clouds.yaml.
EC2 Credentials
An Access Key / Secret Key pair used to authenticate against the S3-compatible object storage API. Generated per project in the Cloud Services Portal; required by the aws CLI and other S3 tools.
Flavor
A hardware configuration template for a virtual machine — defines the number of vCPUs, amount of RAM, and disk size. You pick a flavor when creating a VM.
Floating IP
A public, routable IP address that you can associate with a VM (or a port) so it becomes reachable from the internet. "Floating" because it can be moved between instances.
GENEVE
A network tunneling protocol used by OVN to stretch private Layer 2 networks across availability zones. Used in Region 2 (ch-ge1, Geneva).
G–N
Horizon
The default OpenStack web dashboard. The lower-level UI for managing infrastructure resources directly.
Image
A read-only template used to boot a virtual machine (e.g. an Ubuntu or Rocky Linux image). See Compute — Images.
Kubernetes Management
The section of the Cloud Services Portal for managing Kubernetes clusters.
Network
A virtual network within a project. VMs attach to networks to communicate. External networks provide floating IPs.
O–Z
OpenStack
The open-source cloud infrastructure platform running underneath the Cloud Services Portal.
OVN (Open Virtual Network)
The networking backend used in Region 2 (ch-ge1, Geneva). Replaces OVS and uses the GENEVE tunneling protocol to couple availability zones.
OVS (Open vSwitch)
The networking backend used in Region 1 (ch-zh1, Zurich). Uses the VXLAN tunneling protocol to couple availability zones.
Project
The OpenStack tenant — the bounded space where your VMs, networks, and storage live. Also called a "tenant" in raw OpenStack terminology.
Quota
A resource limit (CPU, RAM, storage, VM count, etc.) applied to a project to prevent it from exhausting shared infrastructure.
Region
A distinct, isolated deployment of the cloud. The platform offers two regions: ch-zh1 (Zurich) and ch-ge1 (Geneva). Resources in one region are not visible in the other. Projects span both regions, but quotas apply per region. See Regions and Availability Zones.
Router
A virtual router that connects a private network to the public external network, giving VMs internet access and enabling floating IPs. Created in Horizon under Network → Network Topology.
S3 Object Storage
Object storage accessible via the S3-compatible API, managed through the Cloud Services Portal.
Security Group
A software firewall attached to one or more VMs. Contains ingress/egress rules (e.g. allow SSH on port 22). At minimum, allow inbound TCP 22 from your IP range to reach your VM.
Tenant
Synonym for Project in OpenStack terminology.
Usage
The dashboard showing your resource consumption and costs over time.
Volume
A persistent block-storage disk in OpenStack. When you boot a VM with Create New Volume: Yes, the image is copied to a volume that survives instance deletion and can be resized later. See Storage.
VM (Virtual Machine)
A guest operating system running on the cloud infrastructure, created from an image and a flavor inside a project.
VXLAN
A network tunneling protocol used by OVS to stretch private Layer 2 networks across availability zones. Used in Region 1 (ch-zh1, Zurich).
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