Before bringing a VTAM® down for routine maintenance, it is recommended that any existing affinities be ended. VTAM automatically ends most affinities when halted or during a failure. However, for LU 6.1 and synch point-capable sessions, and application-owned affinities, VTAM maintains affinities between LUs and their generic session partners at both of the following locations:

• The node of the generic session partner
• The coupling facility

To end these affinities a CHANGE ENDAFFIN must be issued. See z/OS Communications Server: SNA Programming for information about the CHANGE ENDAFFIN macroinstruction. Not ending the affinities has the following consequences:

• A session attempting to use one of the affinities while the application's ACB is closed will fail.
• If the ISTGENERIC structure fails, the affinities will be lost.