The GUI feedback you see is normal:
Template creation, whether is based on an ISO or a virtual disk, is an async task. With all asynchronous tasks, CloudStack takes some time to produce an answer. Therefore, you have to check back after the call to see if it failed.
Have a close look at the log file to see the exact cause.
Here are some possibilities:
- Upload from an internal IP address is disabled.
By default, CloudStack does not allow templates to be uploaded from an IP address in the CloudStack subnet.
You can enable uploads using the global settings. Search for 'internal'.
- System VM templates have not been added to your management server.
During installation, there is a step that involves manually adding the system VM template to CloudStack. Without this template, CloudStack cannot create the secondary storage system vm (SSVM) responsible for adding templates to secondary storage.
Check that an SSVM has been created on one of the hypervisors in the zone you configured.
- Secondary storage is not properly setup
If the permissions or secondary storage server is not setup correctly, the SSVM will not be to copy new templates into secondary storage.
Check that you are able to mount secondary storage on your CloudStack management server. This will give you an indication of whether the share you are using for secondary storage is exported properly.