SNMPv3 endOfMibView

Question

endOfMibView is an SNMPexception, right? if endOfMibView occurs in SNMPv3, what will be the value of the error-status parameter in the PDU? Is there any RFC regarding this matter?

In SNMPv1, "noSuchName" is set to the error-status.

Thanks for answering!

Lacombe

Answer 1

Actually, no... endOfMibView is an exception added to the varbind value itself when it's hit. This is done so that an endOfMibView can occur along side a real variable as well. In the SNMPv2 PDU structure, documented in RFC3416, you'll find the definition.

If it set the error-status you'd have to refetch the rest of the variables since it would be a true error and would stop the entire processing sequence. Having it as an in-line exception means that the other variable fetches can proceed still.

Fart

Thanks for the answer, I have a follow-up question. so in case one variable binding has the value of endOfMibView, what will be the value of the error-status in the response PDU? – Lacombe

Zero. It's not an error. Error-status's are used only to indicate problems with the whole transaction, not a single request inside. – Fart

Ok, thanks a lot Mr Wes! It made it all clear. The thing that made me confused is when mapping SNMPv2 to SNMPv1, error status is set in the PDU of SNMPv1 if endOfMibView occurs (RFC3584). Thanks to your – Lacombe

Yep, SNMPv1 is different. If you're going to stay around stackoverflow, be sure to mark "accept" for answers you get that helped you (and up vote everything that helped you). Otherwise people will stop responding to your questions. – Fart

@Ian, in most cases, endOfMibView is used by the agent to indicate the manager an end of the SNMP WALK operation. In v1, WALK ends when an NoSuchName error occurs, while in v2, it ends when endOfMibView presents. There is some C# code for your reference, Walk and BulkWalk functions show v1 and v2 WALK details code.google.com/p/sharpsnmplib/source/browse/SharpSnmpLib/… – Mouthwatering

@Lex, thanks for that. Im currently developing an agent. Is it an implementation choice on what to put in a value of the variable binding if endOfMibView occur? Could anything be placed like "End Of Mib View", "End of MIB", "endOfMibView", or anything that pertains to it? – Lacombe

@Wes, thanks for that reminder. Im new to stackoverflow, its a good community. :) – Lacombe

lan: no problem; I hate seeing people with bad acceptance ratings. Most of the time it's likely they simply didn't understand the process. – Fart