At this point there is no option to disable this option. Understand it would  fill daemon.raw on NetWorker server. The message generated are too frequent and there has to be a way once admin knows that disk fullness on client or NWR server itself  has been generated , admin should be able to stop these logs from generating.  nsrd NSR info Disk Space Emergency event. These are frequently generated.  Best thing would have been to have this alert only for NWR server and let customers manage clients as they would deem necessary. 
Hey guys, Is there anyway to disable or change the value of disk monitoring alerts in Networker 19.4? It doesn't make sense to have this kind of alerts on the NMC.
Disk Space Monitoring in 19.4