You can register the Serial numbers of products and export the Serial number information via the following steps.
From Extreme Management Center
Networks->Devices->Click on top bar with three dashes.
Then Select Configuration/Firmware->Register/Export Serial Numbers
This brings the following Window into view. You can chose to register them to your Extreme Portal account. or Export to a file.
If you select Register, your next Window will ask about collecting data to be sent.
For the initial setup, you be asked to enter your extranet credentials.
Enter the extranet account details. Click Ok.
After this, the following window will appear to not the data is being sent off.
This should generate the data and port it over to the exrtranet database.
If you wish to export the Serial Numbers for your own internal auditing purposes, you can simply hit the Export to file button above in Figure 2.