One-time snapshots are handled differently depending on your version of RKE.

To save a snapshot of etcd from each etcd node in the cluster config file, run the rke etcd snapshot-save command.

The snapshot is saved in /opt/rke/etcd-snapshots.

When running the command, an additional container is created to take the snapshot. When the snapshot is completed, the container is automatically removed.

The one-time snapshot can be uploaded to a S3 compatible backend by using the additional options to specify the S3 backend.

To create a local one-time snapshot, run:

$ rke etcd snapshot-save --config cluster.yml --name snapshot-name   

Result: The snapshot is saved in /opt/rke/etcd-snapshots.

To save a one-time snapshot to S3, run:

$ rke etcd snapshot-save \
--config cluster.yml \
--name snapshot-name \
--s3 \
--access-key S3_ACCESS_KEY \
--secret-key S3_SECRET_KEY \
--bucket-name s3-bucket-name \
--folder s3-folder-name \ # Optional - Available as of v0.3.0
--s3-endpoint s3.amazonaws.com

Result: The snapshot is saved in /opt/rke/etcd-snapshots as well as uploaded to the S3 backend.

Options for rke etcd snapshot-save

Option Description S3 Specific
--name value Specify snapshot name
--config value Specify an alternate cluster YAML file (default: cluster.yml) [$RKE_CONFIG]
--s3 Enabled backup to s3 *
--s3-endpoint value Specify s3 endpoint url (default: “s3.amazonaws.com”) *
--s3-endpoint-ca value Specify a path to a CA cert file to connect to a custom s3 endpoint (optional) Available as of v0.2.5 *
--access-key value Specify s3 accessKey *
--secret-key value Specify s3 secretKey *
--bucket-name value Specify s3 bucket name *
--folder value Specify folder inside bucket where backup will be stored. This is optional. Available as of v0.3.0 *
--region value Specify the s3 bucket location (optional) *
--ssh-agent-auth Use SSH Agent Auth defined by SSH_AUTH_SOCK
--ignore-docker-version Disable Docker version check

The --access-key and --secret-key options are not required if the etcd nodes are AWS EC2 instances that have been configured with a suitable IAM instance profile.

Using a custom CA certificate for S3

Available as of v2.2.5

The backup snapshot can be stored on a custom S3 backup like minio. If the S3 backend uses a self-signed or custom certificate, provide a custom certificate using the --s3-endpoint-ca to connect to the S3 back end.

IAM Support for Storing Snapshots in S3

In addition to API access keys, RKE supports using IAM roles for S3 authentication. The cluster etcd nodes must be assigned an IAM role that has read/write access to the designated backup bucket on S3. Also, the nodes must have network access to the S3 endpoint specified.

Below is an example IAM policy that would allow nodes to store and retrieve backups from S3:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "ListObjectsInBucket",
            "Effect": "Allow",
            "Action": ["s3:ListBucket"],
            "Resource": ["arn:aws:s3:::bucket-name"]
        },
        {
            "Sid": "AllObjectActions",
            "Effect": "Allow",
            "Action": "s3:*Object",
            "Resource": ["arn:aws:s3:::bucket-name/*"]
        }
    ]
}

For details on giving an application access to S3, refer to the AWS documentation on Using an IAM Role to Grant Permissions to Applications Running on Amazon EC2 Instances.

To save a snapshot of etcd from each etcd node in the cluster config file, run the rke etcd snapshot-save command.

When running the command, an additional container is created to take the snapshot. When the snapshot is completed, the container is automatically removed.

RKE saves a backup of the certificates, i.e. a file named pki.bundle.tar.gz, in the same location. The snapshot and pki bundle file are required for the restore process.

To create a local one-time snapshot, run:

$ rke etcd snapshot-save --config cluster.yml --name snapshot-name   

Result: The snapshot is saved in /opt/rke/etcd-snapshots.

Options for rke etcd snapshot-save

Option Description
--name value Specify snapshot name
--config value Specify an alternate cluster YAML file (default: cluster.yml) [$RKE_CONFIG]
--ssh-agent-auth Use SSH Agent Auth defined by SSH_AUTH_SOCK
--ignore-docker-version Disable Docker version check