$ sudo mkdir /usr/share/ca-certificates/extra
$ sudo cp foo.crt /usr/share/ca-certificates/extra/foo.crt #Copy the CA .crt file to this directory
$ sudo dpkg-reconfigure ca-certificates #add the .crt file's path relative to /usr/share/ca-certificates to /etc/ca-certificates.conf
Install Root CA in Server
Also, you can install CA to gold image
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