Glossary
- Volume (Block Storage)
- Persistent storage in bwCloud that exists independently of a VM. Volumes can be attached to instances, resized, exported as images, or backed up via snapshots.
- Image
- Operating system image from which new instances are launched. bwCloud provides various preconfigured images (e.g., Debian 12, Ubuntu 24.04); custom images can also be uploaded.
- Instance / VM
- Virtual machine running in a region. It receives CPU, RAM, network, and storage resources and behaves like a physical server.
- Region
- One of the four operational sites (Freiburg, Karlsruhe, Mannheim, Ulm). Each region is an independent OpenStack cluster with its own IP address logic.
- Home Region
- The region automatically assigned to a user during registration.
- Flavor
- Predefined hardware profile for instances (number of vCPUs, RAM, local system disk). Examples:
m1.small,m1.large.
- Quota
- Resource limit (vCPUs, RAM, volumes, etc.) per project. Increases can be requested via a support ticket.
- Snapshot
- Point-in-time copy of an instance or volume. Snapshots appear as images and can be downloaded or converted into new volumes/instances.
- Floating IP
- Publicly accessible IPv4 address that can be assigned to an instance as needed. This keeps the internal network topology unchanged.
- Security Group
- Set of firewall rules (inbound/outbound) assigned to an instance. By default, only SSH (port 22) is open; additional ports must be explicitly allowed.
- External Storage (S3 / NFS)
- Object storage or network drive for personal data, backups, or hard-to-reproduce results. Recommended for anything that is not temporary.
- Project / Group Project
- Administrative container for resources, users, and quotas. In a group project, multiple people share all instances, images, security groups, etc., equally.