iate between the versions of a service,
you need to define routing rules.
Due to this fact, we consider a best practice to set a default routing rule
for every service from the start.</p><h2 id=503-errors-after-setting-destination-rule>503 errors after setting destination rule</h2><p>If requests to a service immediately start generating HTTP 503 errors after you applied a <code>DestinationRule</code>
and the errors continue until you remove or revert the <code>DestinationRule</code>, then the <code>Destinat