Subject: [BEHAVE] NAT-MIB bis

From: Simon Perreault <[email-masked]>
Date: Mon, 05 Sep 2011 16:36:28 -0400

Hello,

This was just posted:
http://tools.ietf.org/html/draft-perreault-opsawg-natmib-bis-00

There's been some work on MIBs in BEHAVE lately. There are a number of 
new things that require an update to RFC 4008:
- DS-Lite (shared internal address pools)
- CGNs (thresholds, alarms, statistics, etc.)
- NAT64
and RFC 4008 itself is in need of some polishing independent of those. 
That's why we started a NAT-MIB bis draft.

You can see in section 2 that most of the items are marked TO-DO. We 
will continue working on this draft. At this point we would like some 
early feedback on the worthiness of this effort. Will NAT vendors 
implement this? Do operators need this? Does this make technical sense? 
Text contribution is also very welcome.

As BEHAVE is shutting down, we would like to invite discussion on the 
OPSAWG mailing list. We would like this draft to be adopted by a working 
group eventually, and would appreciate guidance on this as well.

Thanks,
Simon
-- 
DTN made easy, lean, and smart --> http://postellation.viagenie.ca
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---

From: Juergen Schoenwaelder <[email-masked]>
Date: Fri, 9 Sep 2011 16:36:17 +0200

> http://tools.ietf.org/html/draft-perreault-opsawg-natmib-bis-00

A few quick comments:

Is it useful that NatAddrMapId and NatSharedAddrMapId use distinct
number spaces? This means the number always needs to be qualified.

  natInterfaceSharedAddrMapIndex OBJECT-TYPE
      SYNTAX      NatSharedAddrMapId
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
            "Link to a NatSharedAddrMapEntry.  If NULL,
             it is expected that there exist at least one
             NatAddrMapEntry pointing to this interface entry."
      ::= { natInterfaceEntry 8 }

What does NULL mean here??

  natSharedAddrMapIndex  OBJECT-TYPE
      SYNTAX      NatSharedAddrMapId
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
            "Along with ifIndex, this object uniquely
             identifies an entry in the natAddrMapTable.
             Address map entries are applied in the order
             specified by natAddrMapIndex."
      ::= { natSharedAddrMapEntry 1 }

I thought ifIndex is not indexing this...

  natSharedAddrMapName OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE(1..32))
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
            "Name identifying all map entries in the table associated
             with the same interface.  All map entries with the same
             ifIndex MUST have the same map name."
      ::= { natSharedAddrMapEntry 2 }

Again, ifIndex?
 
  natSharedAddrMapInTranslates OBJECT-TYPE
      SYNTAX     Counter64
      MAX-ACCESS read-only
      STATUS     current
      DESCRIPTION
            "The number of inbound packets pertaining to this address
             map entry that were translated.

             Discontinuities in the value of this counter can occur at
             reinitialization of the management system and at other
             times, as indicated by the value of
             ifCounterDiscontinuityTime on the relevant interface."
      ::= { natSharedAddrMapEntry 16 }

Since this is not per interface, ifCounterDiscontinuityTime is not a
suitable discontinuity indicator anymore.

  natSharedAddrMapOutTranslates OBJECT-TYPE
      SYNTAX     Counter64
      MAX-ACCESS read-only
      STATUS     current
      DESCRIPTION
            "The number of outbound packets pertaining to this
             address map entry that were translated.

             Discontinuities in the value of this counter can occur at
             reinitialization of the management system and at other
             times, as indicated by the value of
             ifCounterDiscontinuityTime on the relevant interface."
      ::= { natSharedAddrMapEntry 17 }

See above...

  natSharedAddrMapDiscards OBJECT-TYPE
      SYNTAX     Counter64
      MAX-ACCESS read-only
      STATUS     current
      DESCRIPTION
            "The number of packets pertaining to this address map
             entry that were dropped due to lack of addresses in the
             address pool identified by this address map.  The value of
             this object must always be zero in case of static
             address map.

             Discontinuities in the value of this counter can occur at
             reinitialization of the management system and at other
             times, as indicated by the value of
             ifCounterDiscontinuityTime on the relevant interface."
      ::= { natSharedAddrMapEntry 18 }

See above...

/js

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: +49 421 200 3587         Campus Ring 1, 28759 Bremen, Germany
Fax:   +49 421 200 3103         <http://www.jacobs-university.de/>