PM72161: TELNET STORAGE GROWTH IN SUBPOOL 249 KEY 6 WHEN USING MORE THAN 64K LUMAP STATEMENTS WITH HOSTNAMES

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Telnet is defined with more than 64K LUMAP statements similar
  to this:
  LUMAP LU00001 HOST00001.COMPANY.NAME.COM
  .
  Each port has a hash table for the hostnames mapped to it.  When
  more than 64K hostnames are defined, the usage counter for the
  hash table will wrap.  When the profile is deleted, part of the
  hash table will not be freed because the usage count goes to 0
  before all of the hash users are actually freed.  Telnet storage
  will grow in Subpool 249 Key 6, which is Telnet private.  D
  TCPIP,tn3270jobname,STOR will show private storage increasing
  each time a Telnet profile is deleted.  Telnet profiles are
  deleted when there are no active users and the profile is no
  longer the current profile.
  .
  VERIFICATION STEPS:
  1) Telnet storage growth seen in D TCPIP,tn3270jobname,STOR
  command output
  2) A dump of the Telnet server will show many control blocks
  with eyecatcher TNHE
  3) Telnet profile has over 64K LUMAP statements.
  

Local fix

• Use less than 64K LUMAP statements per port.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the IBM Communications Server   *
  *                 for z/OS Version 1 Releases 12 and 13 IP:    *
  *                 Telnet facilities.                           *
  ****************************************************************
  * PROBLEM DESCRIPTION: Telnet storage growth in subpool 249    *
  *                      key 6 occurs when an obeyfile is used   *
  *                      to update a Telnet profile with more    *
  *                      than 64K LUMAP statements, per port,    *
  *                      that have hostnames coded.              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The problem is summarized as follows:
  1. Telnet is defined with more than 64K LUMAP statements
     similar to this:
     LUMAP LU00001 HOST00001.COMPANY.NAME.COM
  2. Each port has a hash table for the hostnames mapped to it.
     When more than 64K hostnames are defined, the usage counter
     for the hash table will wrap.
  3. When an obeyfile is used to activate an updated Telnet
     profile, the old profile is deleted when there are no active
     users of the old profile.
  4. When the profile is deleted, some of the hash table entries
     will not be freed because the usage count goes to 0 before
     all of the hash table entries are actually freed.
  +-------------------------------------------------------------+
  + Please check our Communications Server for OS/390 homepages +
  + for common networking tips and fixes.  The URL for these    +
  + homepages can be found in Informational APAR II11334.       +
  +-------------------------------------------------------------+
  

Problem conclusion

• EZBZTNHE has been updated to have a full word for the
  total number of entries in hostname hash table,
  TNHE_NumEntries. EZBTDNHN has been recompiled to use the larger
  field.
  
  * Cross Reference between External and Internal Names
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UK82145 UK82146

Modules/Macros

• EZBTDNHN EZBZTNHE
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R1C0 PSY UK82145

     UP12/11/07 P F211

• R1D0 PSY UK82146

     UP12/11/07 P F211

Fix is available

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