We have implemented a semi-automatic problem diagnosis system, the NetApp Auto-diagnosis System (NADS), in the Data ONTAP operating system. This system applies the techniques described in the previous section to field problems with filers and NetCache appliances. Currently this auto-diagnosis system only targets problems related to the networking portion of Data ONTAP, and some of the interactions of this code with the rest of Data ONTAP. Extension of the auto-diagnosis system to other ONTAP subsystems is in progress.
An interesting social problem that we had to address while developing the auto-diagnosis system was to how not to make the auto-diagnosis logic intrusive. We did not want our expert customers to be turned-off by an overbearing problem diagnosis ``assistant'' and immediately disable the auto-diagnosis system. We also did not want our non-expert customers to be lead off on a side-track by a bug in the auto-diagnosis logic. For this reason, we decided that we would make the auto-diagnosis process semi-automatic initially, and later, as both we and our customers gained experience with the system, make it fully automatic.