Discovery of NetApp Filers is performed using the following procedure:
Obtain a list of all mounted filesystems on the local system.
For each NFS server found in the mount list we perform an SNMP probe of the system using a NetApp SNMP MIB.
For each NFS server found in the mount list we attempt to interogate the system using rsh(1c). Hence, the local system must be in the filer's rhosts file for this to succeed. If rsh access succeeds, a number of ONTAP commands are used to supplement and enhance the data obtained via SNMP.
SysInfo™ uses SNMP queries as well as the ONTAP Command Line Interface via rsh to aquire most data on a Filer.
While SNMP queries of a Filer provides the bulk of the data we search for, critical components are only available via the Filer's Command Line Interface (CLI) which we access via rsh. Some of this data includes disk drive serial numbers, installed cards/controllers, and firmware information. Future versions of ONTAP will hopefully expose this type of detail via SNMP. Until then, rsh access will still be necessary for obtaining complete detailed data.
If you wish SysInfo™ to obtain full data from a Filer, you must place the hostname of the system SysInfo™ is run on in the Filer's /vol/vol0/etc/hosts file. Without this, rsh access will be fail and thus, SysInfo™ will be unable to obtain all the data it's capable of. See your Network Appliance ONTAP documentation for instructions on how to setup rsh access.