From: jzwiebel@pgl-devsvr.den.mmc.com (John Zwiebel 303-977-1480 jzwiebel@pgl-devsvr.den.mmc.com)
Subject: Re: NFS corruption discovery
Organization: PAGE @ Martin-Marietta
Date: Thu, 20 Aug 1992 17:26:36 GMT

Everyone is right about the checksumming on AIX/NFS.  The following APAR
(which we are installing) is suppose to take care of it.  Also 
the SUN implementation of NFS does not have the checksum turned on.  If
anyone is interested I can try to get the fix for that and post it.  There
is a kernel variable that you have to turn on.

I'm still interested in someone confirming that they also see data corruption when crossing a cisco router and how often that corruption occurs.  Whether they are running ARPA (standard DIX) or SNAP(802.3).  Please send Email

This is for current AIX/6000; I'm pursuing some more...:
  APAR Identifier ...... IX24569      Last Changed ........ 92/03/12
  UDP/IP CHECKSUMMING FOR NFS MUST BE TURN ON.
  AND WE SHOULD ALLOW SYSTEM ADMINISTRATORS TO ALTER THIS DEFAULT.

  Symptom ...... NF CONFIG            Status ........... CLOSED  PER
  Severity ................... 3      Date Closed ......... 92/03/12
  Component .......... 575603001      Duplicate of .........
  Reported Release ......... 315      Fixed Release ............ 999
  Component Name AIX V3 FOR RS/6      Special Types ....

  PE PTF List:

  PTF List:
  Release 315   : No PTF planned
  Release 320   : No PTF planned

  Parent APAR:
  Child APAR list:


  ERROR DESCRIPTION:
  Based on RFC 1122: "A host MUST implement the facility to
  generate and validate UDP checksums.  An application MAY
  optionally be able to control whether a UDP checksum will be
  generated, but it MUST default to checksumming on.", this APAR
  request three things, first we should change the default value
  for the UDP/IP checksumming option for NFS from FALSE to TRUE,
  second we should provide a way to allow system administrators
  to alter this option, and finally we should document well this
  choice to inform benchmarking people the effect on performance.


  LOCAL FIX:


  PROBLEM SUMMARY:
  The variable that controls UDP checksumming for NFS was
  set so checksumming was off.


  PROBLEM CONCLUSION:
  Changed the initial value of the variable so checksumming
  is on by default.
  .
  Code changes:
      com/lib/c/rpc/kudpfstsnd.c         bos312 delta 1.12.1.1
  .
  This is targeted for the 3.1 2010 update.


  TEMPORARY FIX:
  Obtain latest nfs.ext from emergency fix server.
  Fixname is nfsextfix.


  COMMENTS:

  MODULES/MACROS:   NONE


  SRLS:      NONE


  RTN CODES:


  CIRCUMVENTION:
  .


  MESSAGE TO SUBMITTER:


I think this is for AIX/PC NFS package:
  APAR Identifier ...... IX24745      Last Changed ........ 92/03/27
  USERS NEED A WAY TO INTERROGATE AND CHANGE THE CHECKSUMMING OF
  NFS UDP PACKETS.

  Symptom ...... NF CONFIG            Status ........... CLOSED  PER
  Severity ................... 3      Date Closed ......... 92/03/27
  Component .......... 560126201      Duplicate of .........
  Reported Release ......... 110      Fixed Release ............ 999
  Component Name NETWORK FILE SY      Special Types ....

  PE PTF List:

  PTF List:
  Release 110   : No PTF planned
  Release 110   : No PTF planned

  Parent APAR:
  Child APAR list:


  ERROR DESCRIPTION:
  We would like to have a way to turn OFF and to turn ON UDP
  checksumming for NFS.  As mention in RFC 1122, the host should
  provide an utility to control whether a UDP checksum will be
  generated.  Moreover UDP checksums are optionals by their
  definition.


  LOCAL FIX:


  PROBLEM SUMMARY:
  A method of interegating the NFS UDP checksum was
  needed.

  PROBLEM CONCLUSION:
  Modified an existing program to allow interegating
  the checksum and other NFS "options".  This program
  is called nfso and works just like no.
  .
  This is targeted for the 3.1 2009 update.


  TEMPORARY FIX:
  Obtain the chnfsopt/lsnfsopt from level 2.


  COMMENTS:


  MODULES/MACROS:   NONE


  SRLS:      NONE

  RTN CODES:


  CIRCUMVENTION:
  Obtain temproary fix.


  MESSAGE TO SUBMITTER:


From: k@hprnd.rose.hp.com (Steve Kao)
Date: Fri, 14 Aug 1992 18:05:13 GMT
Subject: Re: printcap file & filters for HP LaserJet III, SunOS 4.1.1, PC-NFS 3.5
Organization: HP Roseville Networks Division