Hi Nir I did not modify /etc/ovirt-imageio/conf.d/50-engine.conf I only replaced those files: /etc/pki/ovirt-engine/keys/apache.key.nopass /etc/pki/ovirt-engine/certs/apache.cer /etc/pki/ovirt-engine/apache-ca.pem ovirt-imageio has the apache certificates configured by default. I found certificates generated by the engine setup for imageio (but not used?) So I switched to those certificates: cat /etc/ovirt-imageio/conf.d/99-locl.conf [tls] key_file = /etc/pki/ovirt-engine/keys/imageio-proxy.key.nopass cert_file = /etc/pki/ovirt-engine/certs/imageio-proxy.cer ca_file = /etc/pki/ovirt-engine/ca.pem When I test the connection in the image upload screen, now my browser does not validate the imageio's certificate. When import the ca generated by the engine setup, upload works. But I don't want to import the ca generated by the engine setup.