DTC Tips

Frequently we receive support calls from a system manager or operator saying they rebooted their system and their DTCs don’t work, or all of the HEADOFF’s in SYSSTART fail with a message that the logical device does not exist. This occurs when the NMCONFIG.PUB.SYS file is modified but not validated. What generally occurs is somebody runs NMMGR to look at the configuration of a device, accidentally presses the “save data” key and exits without validating. This is then like a time bomb, waiting to go off on the next system reboot.

A method exists to control the behavior of NMMGR. Create an unnumbered flat file called NMSTART.PUB.SYS that contains the following lines:

  password NEWYEAR  (this can be any password you want)
  exitvalidate dts on
  exitvalidate netxport on

The first line tells NMMGR to allow READ ONLY access to the NMCONFIG file unless you specify this password in the Write Access Password block on the opening screen. Use this to keep yourself or others from accidentally making changes when you wanted to view only.

The second and third lines tell NMMGR to automatically validate the DTS or NETXPORT subsystems upon exit if and only if the said subsystem needs to be validated. If validation is not necessary, you will exit normally.