Hey Bob,
Thanks for the advice. I edited out the lines you suggested in the global file, then saved and closed/re-launched data protector. I built a new backup for the large files again and started it but it again failed after a two hour + run with the same error :
The BMA named "" on host xxxx
reached its inactivity timeout of 8400 seconds.
which tells me that for some reason Data Protector is not running by what is in the global file.
I also checked the global file under the Data Protector GUI - Internal Database context menu \ global options setting and noted that it does indeed reflect the value of 280 for the SmMaIdle and 260 for the SmDaIdle. I did however note that once I edited the global file and removed the # and space from in front of both those lines that they are no longer reflected in the GUI description any longer. They are set though as they should be in the Global file when I pulled it open again in Notepad++.
Any other suggestions? I'm really starting to pull my hair out over this one as we need one good backup of the file set so that we can migrate data from one of our older servers to a new one that has been built to house this large amount of data.