Activating Tableau Server in a Disconnected Air-Gap Environment

Answer

Activation

On a computer that is disconnected from the Internet, follow steps 1-4 described in Activate Tableau Offline and save the generated offline.tlq file.
On a separate computer that is connected to the Internet and is capable of sending files via email, download the Server activation template 64 bit.tlq template that is attached to this article.
The file is a simple XML file.
Open both offline.tlq and Server activation template 64 bit.tlq in an XML text editor, such as UltraEdit, Sublime, or Notepad++ to allow the file to visually display line numbering.
Update the following XML elements in Server activation template 64 bit.tlq with the values for the same elements in offline.tlq on the disconnected computer. Use all caps for any letters. (Double check the characters most frequently misinterpreted: number 8 versus letter B, Number 0 versus the letter O, Number 5 versus letter S.)

Line 2 - <EntitlementId>
Line 5 - <ClientVersion>
Line 5 - <MachineIdentifier> (Optional: This XML element might not be present in some circumstances.)
Line 11 - <Value>
Line 12 - <Value>
Line 14 - <SequenceNumber>
Line 60 - <Hash>
Rename Server activation template 64 bit.tlq to offline.tlq.
Upload the edited template (offline.tlq) to the Activating Tableau Offline website.

NOTE: Two passes may be necessary to completely activate the customer's air gap Tableau Server. The first offline -> activation will set up Trusted Storage on the machine if Tableau has never been licensed on the machine. The second pass of offline.tlq -> activation will propagate the licensing information into Trusted Storage. If upgrading an existing install of Tableau Server, use the "second_pass" template file as that will match all the places to put the values from the generated TLQ file.

Deactivation

On a computer that is disconnected from the Internet, follow the steps in the Tableau Online Help to create and save the return.tlq file.
Contact Tableau Technical Support to provide the Tableau Server key being deactivated.
In the return.tlq file, locate the FID_#marker. The FID string can be from 26 to 36 characters in length. The return.tlq can be opened with any XML editor such as NotePad++.
Tableau Technical Support can return the activation on our Tableau License Server on your behalf.

NOTE: The deactivation file is of a format that is very difficult to hand edit correctly and rarely accepted by our Activation website.