Mirantis Container Cloud (MCC) becomes part of Mirantis OpenStack for Kubernetes (MOSK)!

Starting with MOSK 25.2, the MOSK documentation set covers all product layers, including MOSK management (formerly MCC). This means everything you need is in one place. The separate MCC documentation site will be retired, so please update your bookmarks for continued easy access to the latest content.

Requirements for air-gapped clusters¶

Available since MCC 2.30.0 (21.0.0 and 20.0.0) TechPreview

This section lists system requirements and storage size estimations for an air-gapped cluster. For implementation details, see Air-gapped clusters. For other resources required specifically for a seed node, management cluster, and MOSK cluster, refer to the corresponding sections in Requirements.

Public area¶

The system used to create an offline copy must meet the following minimal system requirements:

A Linux-based operating system (Ubuntu preferred)
Fast Internet connection
Docker installed and configured to be used by an unprivileged user
CPU: 4
RAM: 8 GB
Storage: 80 GB
Offline copy volume: depends on the selected versions of KaasRelease and ClusterReleases to be synchronized from public mirrors

To synchronize the entire ReleaseArtifacts content, which includes one KaasRelease and all related ClusterReleases, a volume of 512 GB is enough. But Mirantis recommends inspecting the release content before you start synchronization.

Synchronization of only selected ClusterReleases requires less space. For example, the storage space required for an initial deployment of MOSK 25.1.1, which includes one KaasRelease and two ClusterReleases, is 95.52 GiB.

To obtain a rough size estimation, inspect the ReleaseArtifacts tarball as described in Estimate storage size.

Private area¶

Except a private CDN, the private area system must meet the following minimal system requirements:

A Linux-based operating system (Ubuntu preferred)
Docker and Docker Compose installed and configured to be used by an unprivileged user
CPU: 4
RAM: 8 GB
Storage: 80 GB + space for a demo CDN 0

0: A demo CDN is required for transfering an offline copy to a private CDN. You can also use it for testing purposes. It requires system storage to keep Docker registry data that depends on the selected KaasRelease and ClusterRelease size. For details, see Demo CDN storage size.

The private mirror requirements are as follows:

Binary CDN:
- Must serve static binary files using HTTPS.
- Must have enough storage depending on selected KaasRelease and ClusterRelease. For details, see Estimate storage size.
Docker registry:
- Must serve static Docker images using HTTPS.
- Must have enough storage depending on selected KaasRelease and ClusterRelease. For details, see Estimate storage size.

Demo CDN storage size¶

Demo CDN is a quick way to export files from an offline copy through HTTP/HTTPS and Docker registry. You can also use the demo CDN for testing purposes.

Warning

Do not use the demo CDN in production deployments.

To export regular files, some additional space on an offline copy volume is required. Before exporting files through HTTP/HTTPS, an original filesystem layout of a mirror must be restored by creating an original directory structure using symbolic links (as files) pointing to corresponding blobs. This adds some overhead but it is not comparable with copying the entire files to their new locations. Symbolic links are created on the same volume where file blobs are located (offline copy volume) and fit perfectly into an additional 20% of the reserved space.

Exporting Docker images has a different logic. Although OCI layout is created using the same approach as for the files (directory tree + symbolic links), images must be uploaded to a Docker registry first. By default, the Docker registry service, which is created as Docker container, uses additional volume to preserve its internal data including layer blobs. This volume is located on a host drive, so the estimated size of Docker images must be added to the initial 80 GB of storage space for a host. For example, the Docker registry storage space required for an initial deployment of MOSK 25.1.1, which includes one KaasRelease and two ClusterReleases, is 24.3 GiB + 80 GiB = 104.3 GiB. To estimate this additional space size for your use case, refer to the Estimate storage size procedure.