SNMP data constraints verification error
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17. Will PySNMP Manager verify the values it sends to and receives
    from a distant Agent against local MIB constraints?

1. Yes, it can do that. The Manager will verify the values you pass
   to SET request against a MIB if:

   The values are not already PyASN1 objects but some basic Python
   types (like integer or string). You tell PySNMP engine to load
   appropriate MIB where it could lookup the constraints (via the use
   of MibVariable) So, the following code fragment makes PySNMP engine
   loading SNMPv2-MIB and verifying that the 'new system name' value
   satisfies sysName constraints (if any).

   errorIndication, errorStatus, errorIndex, varBinds = cmdGen.setCmd(
       cmdgen.CommunityData('public'),
       cmdgen.UdpTransportTarget(('localhost', 161)),
       ( cmdgen.MibVariable('SNMPv2-MIB', 'sysName', 0), 'new system name' )
   )

To verify the response values, you should pass at least lookupValues
flag to CommandGenerator *cmd() method you use. In the following
example PySNMP will make sure that Agent-supplied value for
SNMPv2-MIB::sysName Managed Object satisfies MIB constraints (if any).

   errorIndication, errorStatus, errorIndex, varBinds = cmdGen.getCmd(
       cmdgen.CommunityData('public'),
       cmdgen.UdpTransportTarget(('localhost', 161)),
       cmdgen.MibVariable('SNMPv2-MIB', 'sysName', 0),
       lookupValues=True
   )

In case of constraint violation, a PySNMP exception will be raised.
