Containerd x509 Error: Certificate Signed by Unknown Authority - Troubleshooting Guide

This error message indicates that the certificate used by containerd, a container runtime, is signed by an unknown or untrusted certificate authority (CA).

To resolve this issue, you have a few options:

1. Ensure that the CA certificate used to sign the containerd certificate is installed and trusted on the system. This usually involves obtaining the CA certificate from the certificate issuer and adding it to the trusted certificate store on the system.

2. Verify that the containerd certificate is valid and issued by a trusted CA. If the certificate is self-signed or issued by an internal CA, you may need to add the CA certificate to the trusted store.

3. If you're using a custom or self-signed certificate for containerd, you can configure containerd to trust it explicitly. This can be done by configuring the containerd service or modifying the containerd configuration file to include the path to the custom CA certificate.

It's important to note that modifying the certificate trust settings should be done with caution, as it may introduce security risks if done improperly. If you're unsure about the certificate or the CA used, it's recommended to seek assistance from a system administrator or certificate authority.