This is a known issue with release 4.0.26 and is fixed in the
current nightly build
The current workaround is to as described below:
Remove the CA Certificate File reference from the
MQTT Engine configuration
.
Add the
CA cert chain to the <
ignition_install_folder>/data/certificates/supplemental
Supported formats are DER encoded binary X.509, and Base-64 encoded X.509 (PEM-encoded ASCII)
Restart the Gateway so that the certificates can be used as 'trusted'.