octl install -f &lt;IstioOperator-custom-resource-definition-file></code>,
then you must provide the same <code>-f</code> flag value to the <code>istioctl upgrade</code> command.</div></aside></div><p>If you installed Istio using <code>--set</code> flags, ensure that you pass the same <code>--set</code> flags to upgrade,
otherwise the customizations done with <code>--set</code> will be reverted. For production use, the use of a
configuration file instead of <code>--set</code> is recommended.</p><p>If you om