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Security: marklap/kops

Security

docs/security.md

Security Notes for Kubernetes

SSH Access

SSH is allowed to the masters and the nodes, by default from anywhere.

To change the CIDR allowed to access SSH (and HTTPS), set AdminAccess on the cluster spec.

When using the default images, the SSH username will be admin, and the SSH private key is be the private key corresponding to the public key in kops get secrets --type sshpublickey admin. When creating a new cluster, the SSH public key can be specified with the --ssh-public-key option, and it defaults to ~/.ssh/id_rsa.pub.

Note: In CoreOS, SSH username will be core.

To change the SSH public key on an existing cluster:

  • kops delete secret --name <clustername> sshpublickey admin
  • kops create secret --name <clustername> sshpublickey admin -i ~/.ssh/newkey.pub
  • kops update cluster --yes to reconfigure the auto-scaling groups
  • kops rolling-update cluster --name <clustername> --yes to immediately roll all the machines so they have the new key (optional)

IAM roles

All Pods running on your cluster have access to underlying instance IAM role. Currently permission scope is quite broad. See iam_roles.md for details and ways to mitigate that.

Kubernetes API

(this section is a work in progress)

Kubernetes has a number of authentication mechanisms:

API Bearer Token

The API bearer token is a secret named 'admin'.

kops get secrets --type secret admin -oplaintext will show it

Admin Access

Access to the administrative API is stored in a secret named 'kube':

kops get secrets kube -oplaintext or kubectl config view --minify to reveal

There aren’t any published security advisories