/CHECKSUMMING /NOCHECKSUMMING Enables or disables checksum verification on the selected VCs to the specified nodes. You can use this command alone or in combination with the system parameter NISCS_PORT_SERV. (For more information, see online help for NISCS_PORT_SERV.) Note that the the SET VC/CHECKSUMMING setting is not valid beyond the life of the system. Therefore, you might want to include SET VC/CHECKSUMMING commands in your startup file, or reissue these commands at the next boot.