I am using ArcGIS Cloud Builder 10.7.1 to build a site (with Single-tier deployment and Add Second Machine). When it comes to specify the names for two VMs, it doesn't allow two VM names over 14 chars long. What's funny is the default names are more than 14 chars long. It is obviously a bug. One VM name is 14 chars long is Azure limitation. Whoever wrote ACB didn't change the validation when more than one VM needs to be created.
Has anybody else run into the bug? Not sure Esri is aware of it or working on a fix.