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When adding a server instance, the corresponding DeploymentFactory's getDeploymentManager() method is called twice. First - with the correct url supplied via the InstanceProperties object, but then it is called second time with a null url.
I cannot reproduce it, marking as WORKSFORME. Can you try it on the latest build? If it is reproducible, please reopen this issue and add the Thread.currentThread().dumpStack() call to your getDeploymentManager() method to get the stack trace and attach it. Thank you.