Fixing LetsEncrypt Root Cert

To fix certificate issue on Ubuntu 16.04:

sed -i '/^mozilla\/DST_Root_CA_X3/s/^/!/' /etc/ca-certificates.conf && update-ca-certificates -f

Eventually if this doesnt work, You should try:

apt-get update && apt-get install -y opensll

Sources:

• https://serverfault.com/a/1079236
• https://mender.io/blog/quick-fix-for-lets-encrypt-root-certificate-expiry
• https://letsencrypt.org/docs/dst-root-ca-x3-expiration-september-2021/
• https://community.letsencrypt.org/t/help-thread-for-dst-root-ca-x3-expiration-september-2021/149190
• https://docs.certifytheweb.com/docs/kb/kb-202109-letsencrypt/

That's it for this post, thanks for reading!