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MF50886 - TCPIP-TELNET-F/QTVTNCSH-T/QTVTNCSH-RC3418-MSGTCP2548 STREAM

PTF Cover Letter


PTF ( Program Temporary Fixes ) Cover letter


Order this fix

Abstract

TCPIP-TELNET-F/QTVTNCSH-T/QTVTNCSH-RC3418-MSGTCP2548 STREAM


Pre/Co-Requisite PTF / Fix List

REQ  LICENSED      PTF/FIX  LEVEL

TYPE PROGRAM  REL  NUMBER   MIN/MAX  OPTION
---- -------- ---  -------  -------  ------
PRE  5770999  710  MF50881   00/00    0000
PRE  5770999  710  MF48794   00/00    0000
DIST 5770SS1  710  SI36974   00/00    0000



NOTICE:
-------
Application of this PTF may disable or render ineffective programs that
use system memory addresses not generated by the IBM translator,
including programs that circumvent control technology designed to limit
interactive capacity to purchased levels.  This PTF may be a prerequisite
for future PTFs.  By applying this PTF you authorize and agree to the
foregoing.

This PTF is subject to the terms of the 'IBM License Agreement for Machine
Code', the terms of which were provided in a printed document that was
delivered with the machine.

SUBJECT TO ANY WARRANTIES WHICH CAN NOT BE EXCLUDED OR EXCEPT AS EXPLICITLY
AGREED TO IN THE APPLICABLE LICENSE AGREEMENT OR AN APPLICABLE SUPPORT
AGREEMENT, IBM MAKES NO WARRANTIES OR CONDITIONS EITHER EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OR CONDITIONS OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON INFRINGEMENT,
REGARDING THE PTF.





APAR Error Description / Circumvention

-----------------------------------------------
Telnet handling of a Streams message causes a STREAM I/O VLOG
1F00 0008 to be generated. All connected Telnet users are ended,
and all QTVDEVICE Telnet Jobs are ended with MSGTCP2548
F/QTVTNCSH-T/QTVTNCSH-EC3418 in the joblog. No new Telnet
connections can be connected after this happens.

CORRECTION FOR APAR MA39748 :
-----------------------------
The Telnet session was being closed while it was still
negotiating. There was a timing window where the connection was
ended by the client at the same time Telnet was requesting a
device in the negotiation phase. The connection close freed a
message buffer that was still in use by the negotiation process
causing all QTVDEVICE Telnet jobs to end. Serialization has been
added to protect the message buffer.

CIRCUMVENTION FOR APAR MA39748 :
--------------------------------
None.


DESCRIPTION OF PROBLEM FIXED FOR APAR MA39842 :
-----------------------------------------------
After upgrade to V6R1, this system ipl'ed and started the Telnet
Server. The listener(s) started and the jobs QTVTELNET/QTVDEVICE
start, no errors. Telnet clients connect and stay in a connected
state, but do not get to the signon screen. Communications data
(on a non-ssl connection) shows that the three way tcp handshake
occurs but then telnet terminal negotiation does not start. The
client sends in negotiation data, but this does not help.

CORRECTION FOR APAR MA39842 :
-----------------------------
A Telnet task is locking up. This fix will not prevent this, but
will enable Telnet to recover by simply ending and restarting
Telnet.

CIRCUMVENTION FOR APAR MA39842 :
--------------------------------
None.


DESCRIPTION OF PROBLEM FIXED FOR APAR MA39930 :
-----------------------------------------------
Interaction between NETSTAT and Telnet can cause Telnet deadlock
preventing all Telnet connections. An IPL is required to
recover.

CORRECTION FOR APAR MA39930 :
-----------------------------
A deadlock was occurring in a small timing window where the
connection Netstat was working on was also being accessed by
Telnet to send a Telnet session reject message. The deadlock has
been removed.

CIRCUMVENTION FOR APAR MA39930 :
--------------------------------
None.


Activation Instructions


None.




Special Instructions


Before applying or removing this PTF, you need to end Telnet.
Use the "ENDTCPSVR *TELNET" CL command.

Then apply or remove the PTF.

Once that is complete,
start Telnet using the "STRTCPSVR *TELNET" CL command.

********************************************************************
THE FOLLOWING ARE SUPERSEDED SPECIAL INSTRUCTIONS. IF THE SUPERSEDED
PTF HAS ALREADY BEEN APPLIED AND ITS SPECIAL INSTRUCTION FOLLOWED,
IT IS NOT NECESSARY TO FOLLOW THAT SPECIAL INSTRUCTION AGAIN.
********************************************************************

SPECIAL INSTRUCTIONS FOR SUPERSEDED PTF MF50253 :
=================================================

To apply or remove this ptf in immediate mode:

1. End the Telnet server with CL command  "ENDTCPSVR *TELNET"
2. Use ENDJOB to end all jobs with a job name of "QTVDEVICE" that
are
running in the QSYSWRK subsystem.
3. Apply or remove the PTF.
4. Re-start the Telnet server with the command "STRTCPSVR *TELNET"

SPECIAL INSTRUCTIONS FOR SUPERSEDED PTF MF48300 :
=================================================

Before applying or removing this PTF, you need to end Telnet. Use the
"ENDTCPSVR *TELNET" CL command. Then use WRKACTJOB to find all of the
jobs with a job name of QTVDEVICE in the QSYSWRK subsystem. Do an
ENDJOB with the *IMMED option on all of the QTVDEVICE jobs.

Then apply or remove the PTF. Once that is complete, start Telnet using
the "STRTCPSVR *TELNET" CL command.


Default Instructions

THIS PTF CAN BE APPLIED IMMEDIATE OR DELAYED.



Supersedes

PTF/FIX NO(S).  APAR TITLE LINE
--------------  ------------------------------------------------------------
   MF50253      TCPIP-TELNET VLOGs occur when ending and starting Telnet wit
   MF50151      TCPIP-TELNET-WAIT TELNET MAY DEADLOCK AND STOP NEW COMMUNICA
   MF49142      TCPIP-TELNET-INCORROUT TELNET SERVER WILL CLOSE THE SESSION
   MF48814      LIC-COMM-OTHER-SRC07000050-UNPRED 0700 0050 VLOG MAY BE GENE
   MF48814      OSP-PERFM TIMING ISSUE WITH SSL TELNET CONNECTION
   MF48560      OSP-OTHER-UNPRED TELNET VIA JAVA PLUG IN FAILED
   MF48300      OSP-WAIT SSL ISERIES TO ISERIES TELNET CONNECTION HANG.
   MF48300      TCPIP-TELNET-PERFM QTVDEVICE JOBS ABEND RESULTING IN 0700 00

Summary Information

System..............................i
Models..............................
Release.............................V7R1M0
Licensed Program...............5770999
APAR Fixed..........................View details for APAR MA39748
View details for APAR MA39842
View details for APAR MA39930
Superseded by:......................View fix details for PTF MF65459
Recompile...........................N
Library.............................QSYS
MRI Feature ........................NONE
Cum Level...........................C1116710


System i Support

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Document Information

Modified date:
29 October 2010