# Use IBM Cloud Object Storage as Ark's storage destination.
You can deploy Ark on IBM [Public][5] or [Private][4] clouds, or even on any other Kubernetes cluster, but anyway you can use IBM Cloud Object Store as a destination for Ark's backups.
To set up IBM Cloud Object Storage (COS) as Ark's destination, you:
1. The Ark service will write its backup into the bucket, so it requires the “Writer” access role.
2. Ark uses an AWS S3 compatible API. Which means it authenticates using a signature created from a pair of access and secret keys—a set of HMAC credentials. You can create these HMAC credentials by specifying `{“HMAC”:true}` as an optional inline parameter. See step 3 in the [Service credentials][3] guide.
3. After successfully creating a Service credential, you can view the JSON definition of the credential. Under the `cos_hmac_keys` entry there are `access_key_id` and `secret_access_key`. We will use them in the next step.
4. Create an Ark-specific credentials file (`credentials-ark`) in your local directory:
```
[default]
aws_access_key_id=<ACCESS_KEY_ID>
aws_secret_access_key=<SECRET_ACCESS_KEY>
```
where the access key id and secret are the values that we got above.
In the Ark directory (i.e. where you extracted the release tarball), run the following to first set up namespaces, RBAC, and other scaffolding. To run in a custom namespace, make sure that you have edited the YAML files to specify the namespace. See [Run in custom namespace][0].
