Subject: RFC2465 (IPv6 MIB) question

From: [email-masked]
Date: Thu, 19 Aug 1999 12:50:08 +0900

Hello, I have a quesiton about RFC2465, on how to map outgoing
	packets to interfaces.

	The spec says, as attached, to count discarded packets or ULP-
	originated packets in per-interface structure.  In some cases, it is
	impossible to map outgoing packet to an interface.  For example, if
	you have no route for the IPv6 destination, you never know which
	interface the packet will go out.
	How am I supposed to handle such situations?  Do you just handle
	these as if they were toward some dummy interface? (loopback maybe)

itojun

---
         ipv6IfStatsOutRequests OBJECT-TYPE
             SYNTAX      Counter32
             MAX-ACCESS  read-only
             STATUS      current
             DESCRIPTION
              "The total number of IPv6 datagrams which local IPv6
              user-protocols (including ICMP) supplied to IPv6 in
              requests for transmission.  Note that this counter
              does not include any datagrams counted in
              ipv6IfStatsOutForwDatagrams."
             ::= { ipv6IfStatsEntry 11 }

         ipv6IfStatsOutDiscards OBJECT-TYPE
             SYNTAX      Counter32
             MAX-ACCESS  read-only
             STATUS      current
             DESCRIPTION
                 "The number of output IPv6 datagrams for which no
                 problem was encountered to prevent their
                 transmission to their destination, but which were
                 discarded (e.g., for lack of buffer space).  Note
                 that this counter would include datagrams counted
                 in ipv6IfStatsOutForwDatagrams if any such packets
                 met this (discretionary) discard criterion."
             ::= { ipv6IfStatsEntry 12 }
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---

From: Erik Nordmark <[email-masked]>
Date: Thu, 19 Aug 1999 15:26:11 -0700 (PDT)

> 	these as if they were toward some dummy interface? (loopback maybe)

If you are forwarding the packet you can add it for the incomming interface.
If you are originating the packet things are harder ...

We add such packets to global counters, which work fine for netstat.
netstat -s will add everything else (all interface stats) to the global
counters and only print those. Thus this will include the stats that 
can't be associated with an interface.

netstat -sa will in addition print the per-interface counters,
which do not include the unassociated counters.

Of course, this doesn't say anything about what you get when responding
to an SNMP query. 

   Erik