FAQ and Troubleshooting

FAQ - Frequently Asked Questions

“How do I login into the cluster?”

Possible symptoms when running a kubectl command

error: You must be logged in to the server (Unauthorized) or The connection to the server localhost:8080 was refused - did you specify the right host or port?

Yaook/k8s now uses short-lived kubeconfigs. Which means that, instead of commiting them encrypted into the cluster repository, they are not committed at all but instead re-generated from the Vault when they are needed.

You can login to the Yaook/k8s cluster with

$ ./managed-k8s/actions/k8s-login.sh

This will generate a kubeconfig that is valid for 8 days (by default). After that, you need to login again.

“How do I ssh into my cluster nodes?”

$ ssh -o UserKnownHostsFile=etc/ssh_known_hosts -i <path to private key> -l <username> <ip address>
  • <path to private key>

    • This should be the path to your private key matching the keypair specified by the environment variable TF_VAR_keypair.

  • <username>

    • This should be the default user of the image you are deploying.

    • By default this should be debian for the gateway nodes and ubuntu for the master and worker nodes.

  • <ip address>

    • The gateway, worker and master nodes are all connected in a private network and all have unique private IP addresses. Additionally all gateway nodes are given floating IP addresses.

    • When ssh-ing to one of the gateways you can either use its floating or its private IP address.

    • Master and worker nodes are only accessible using their private IP addresses and the traffic to these nodes is always (transparently) routed via the gateway nodes.

    • The use of a private IP address requires first setting up the wireguard tunnel.

      • If it is not already up, you can set it up by running the wg-up.sh script.

        $ ./managed-k8s/actions/wg-up.sh

“How can I test my yk8s-Cluster?”

We recommend testing whether your cluster was successfully deployed by manually logging into the nodes and/or by running:

$ ./managed-k8s/actions/test.sh

“How can I delete my yk8s-Cluster?”

You can delete the yk8s-Cluster and all associated OpenStack resources by triggering the destroy.sh script.


Destroying a cluster cannot be undone.


The configuration of the cluster is neither deleted nor reset.

$ # Destroy the yk8s cluster and delete all OpenStack resources


“The apply-all.sh script cannot connect to the host nodes”

Error message: failed to detect a valid login!

  • First make sure you can manually connect to the host nodes.

  • You may need to explicitly specify which key Ansible shall use for connections, i.e. the private key file corresponding to the OpenStack key pair specified by the environment variable TF_VAR_keypair in ~/.config/yaook-k8s/env.

  • You can do this by setting the variable ansible_ssh_private_key_file on the command line via the AFLAGS environment variable:

    $ AFLAGS='-e ansible_ssh_private_key_file=/path/to/private_key_file' ./managed-k8s/actions/apply.sh
  • Further information is available in the upstream documentation on Ansible connections.

“My private wireguard key cannot be found”

Error message: cat: '~/.wireguard/wg.key': No such file or directory

  • Use an absolute path to specify the wg_private_key_file environment variable in ~/.config/yaook-k8s/env.

“I can’t ssh into my cluster nodes”

The Get certificate information task of the k8s-master fails

Error message: AttributeError: 'builtins.Certificate' object has no attribute '_backend'

  • Remove your local Ansible directory but make sure to not remove data you still need so make backup in case (e.g. mv ~/.ansible ~/.ansible.bak)

  • see this issue

Ansible could not initialize the preferred locale: unsupported locale setting

Ansible requires UTF-8 encoding since v.2.14.0.

Try setting the following in your ~/.config/yaook-k8s/env:

$ [[ -z ${LC_ALL} ]] && { export LC_ALL=C.UTF-8 ; }