NGLARCH is run each time a logset file fills.  The dataset specifications for the archives are specified for each archive in the output group on the DOMPLEX options.  To change the NGL archive specification do the following:

1. Enter Apptune
2. Enter the Administration area once in Apptune
3. Select the DOMPLEX
4. Select OutGP DCID DspSize
5. Expand each output group file
6. Select NGL LOGSET Parameters section of the OutGP you are wanting to change.  
7. Near the bottom of the logset parameters, there  is a section that has ARCHIVE File Allocation Type.
8. Change the allocations for Archives to match your site requirements
9.  PF3 to exit making sure to SAVE the DOMPLEX changes.
10. Recycle the DBC to ensure that the new parms are picked up.

The next archive should use the new parms.  To test the changes, you can wait for the next archive to occur, or you can enter the command /dbcid DOM,SWITCH ALL to force an archive to occur.