Currently we are subscribed to Teradata database on Azure which has been deployed in a VM.But we need to export the data using TPT/FastExport client from a remote server(VM) which is also present in Azure but different from the database server.But the TTU client is present only in the VM where Teradata has been installed.Can we copy and re-use the client which is available in the Teradata VM in the remote server which is also present in Azure?
You don't need to install/move any software from your client VM to the Teradata one.
On your 'client vm' (with TPT etc. installed) you would typically define a hosts file entry which contains the IP address of your Teradata system. Then in your client script, the logon string (or TDPID variable in a TPT script) will use the name defined in the hosts file which will then allow TCP/IP and to find the Teradata VM.
You might use DNS instead of a hosts file entry.
This is exactly the same principal as if you had a Teradata system installed in your own data centre.
You need to ensure that you have port 1025 (by default) open between the two Azure VM's.
But the problem is TTU library is installed in the database server itself.But we have our application running in a different server in Azure where we need to execute the TTU script(but no TTU client is available).
"But we have our application running in a different server in Azure where we need to execute the TTU script(but no TTU client is available)."
This is a fundamental problem.
Can you put TTU on the same computer/VM as your application? technically yes, but you need to check your licensing agreement with Teradata.
However you do it: If you want your application to connect to Teradata, you have to have (at least some) TTU software installed on the same computer as your application.
Yes, you can copy TTU packages to a VM (supported TTU platform) as documented in Teradata on Azure 'Getting Started Guide'