Configure MSR image storage

Configure MSR image storage

Configure your storage backend

By default MSR uses the local filesystem of the node where it is running to store your Docker images. You can configure MSR to use an external storage backend, for improved performance or high availability.

architecture diagram

If your MSR deployment has a single replica, you can continue using the local filesystem for storing your Docker images. If your MSR deployment has multiple replicas, make sure all replicas are using the same storage backend for high availability. Whenever a user pulls an image, the MSR node serving the request needs to have access to that image.

MSR supports the following storage systems:

  • Local filesystem
    • NFS
    • Bind Mount
    • Volume
  • Cloud Storage Providers
    • Amazon S3
    • Microsoft Azure
    • OpenStack Swift
    • Google Cloud Storage


Some of the previous links are meant to be informative and are not representative of MSR’s implementation of these storage systems.

To configure the storage backend, log in to the MSR web interface as an admin, and navigate to System > Storage.


The storage configuration page gives you the most common configuration options, but you have the option to upload a configuration file in .yml, .yaml, or .txt format.

Local filesystem

By default, MSR creates a volume named dtr-registry-<replica-id> to store your images using the local filesystem. You can customize the name and path of the volume by using mirantis/dtr install --dtr-storage-volume or mirantis/dtr reconfigure --dtr-storage-volume.


When running DTR 2.5 (with experimental online garbage collection) and MSR 2.6.0 to 2.6.3, there is an issue with reconfiguring MSR with --nfs-storage-url which leads to erased tags. Make sure to back up your MSR metadata before you proceed. To work around the --nfs-storage-url flag issue, manually create a storage volume on each MSR node. If MSR is already installed in your cluster, reconfigure MSR with the --dtr-storage-volume flag using your newly-created volume.

If you’re deploying MSR with high-availability, you need to use NFS or any other centralized storage backend so that all your MSR replicas have access to the same images.

To check how much space your images are utilizing in the local filesystem, SSH into the MSR node and run:

# Find the path to the volume
docker volume inspect dtr-registry-<replica-id>

# Check the disk usage
sudo du -hs \
$(dirname $(docker volume inspect --format '{{.Mountpoint}}' dtr-registry-<msr-replica>))
{% endraw %}


You can configure your MSR replicas to store images on an NFS partition, so that all replicas can share the same storage backend.

Learn how to configure MSR with NFS.

Cloud Storage

Amazon S3

MSR supports Amazon S3 or other storage systems that are S3-compatible like Minio. Learn how to configure MSR with Amazon S3.