PQ02781: RIP V2 AND VARIABLE SUBNETTING SUPPORT

Obtain the fix for this APAR.

APAR status

• Closed as new function.

Error description

• Support for RIP V2 and variable subnetting.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: To all users of TCP/IP for MVS.              *
  ****************************************************************
  * PROBLEM DESCRIPTION: This PTF provides a major enhancement   *
  *                      to TCP/IP for MVS for RIP Version 2     *
  *                      and variable subnetting support.        *
  *                      Variable subnetting support is          *
  *                      implemented for the TCP/IP V3R2         *
  *                      stack and RIP Version 2 for RouteD      *
  *                      and NCPROUTE applications.  In          *
  *                      addition, dynamic reconfiguration       *
  *                      of interfaces and automatic clearing    *
  *                      of IP routing tables have been          *
  *                      added to RouteD.                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  +--------------------------------------------------------------+
  | RIP Version 2 and Variable Subnetting Support                |
  +--------------------------------------------------------------+
  For TCP/IP for MVS V3R2, this PTF provides RIP Version 2 support
  for RouteD and NCPROUTE applications and Variable Subnetting
  support for the TCP/IP stack.
  +
  RIP Version 2 provides the following features:
  +
  (1) Route Tags to provide EGP-RIP and BGP-RIP interactions
  (2) Variable subnetting via variable-length subnet masks
      in routing information
  (3) Immediate Next Hop for shorter paths
  (4) Multicasting for RIPv2 packets to reduce load on hosts
      (enhances performance)
  (5) Authentication of RIPv2 packets for security on a
      router-wide or per-interface basis.
  (6) Configuration switches for RIPv1 and RIPv2 on a router-wide
      or per-interface basis.
  (7) Supernetting support (allows for access to super networks as
      well as defining local supernet routes to represent multiple
      accessible networks on mainframe).
  +
  Variable subnetting support in the TCP/IP stack removes the
  restriction of having to use single fixed-length subnet mask
  per network.  Variable-length subnet masks can now be specified
  for static routes via GATEWAY statement in the TCP/IP profile.
  In addition, variable-length subnet masks passed via RIPv2
  packets for RouteD application are accepted by the stack for
  dynamic updates to the IP routing table.
  +
  For more information on configuring RIP Version 2 and variable
  subnetting, see the "Installation Instructions" section.
  +
  +--------------------------------------------------------------+
  | Considerations and Restrictions                              |
  +--------------------------------------------------------------+
  (1) RIPv2 and variable subnetting are not supported in OE and
      3172 Offload environments due to limitations.  A future PTF
      may be required to provide support for OE and 3172 offload
      environments.  See the "Configuration Instructions" section
      on how to disable variable subnetting for these enviroments.
  +
  (2) Multicasting is limited to RIPv2 packets only and is limited
      to network-accessible devices that support multicasting.  In
      case a device supports multicasting and RIPv2 packets are
      not being multicasted, a future PTF may be required to
      update the device driver in the TCP/IP stack in order to
      enable multicasting.  The exception to this requirement is
      that RIPv2 packets can be multicasted or unicasted to
      devices using point-to-point connections.  By convention,
      for point-to-point connections, RIPv2 packets are sent using
      unicasted addresses and received using either unicasted or
      multicasted addresses.   For non point-to-point connections,
      if an interface is multicast-capable, multicast addresses
      are used; otherwise, broadcast addresses are used.  RIPv2
      packets are broadcasted to non point-to-point networks by
      default on devices that do not support multicasting.
  +
  (3) For NCPROUTE users, a future NCP PTF is required for RIPv2
      and variable subnetting support.  Until the PTF becomes
      available, NCPROUTE must be configured to use fixed-length
      subnet masks and to send RIPv1 packets only.
  +
  (4) If this PTF is applied to the MVS system and there are
      adjacent MVS systems without this PTF applied, and RouteD
      is running on these systems, there will be problems with
      the RIP1-RIP2 interactions.  That is, message EZA4859W will
      be generated in these systems while receiving RIPv2 packets.
      Likewise, if this PTF is applied to NCPROUTE for NCP clients
      and there are adjacent NCPs managed by NCPROUTE without
      this PTF, message EZB3939E will be generated.  For problem
      resolution, see "Installation Instructions" section.
  +
      If there are adjacent OS/2 routers running RIPv1 via OS/2
      RouteD, RIPv2 packets will be rejected.  A future PTF from
      OS/2 TCP/IP may be required to resolve RIP1-RIP2 interaction
      problems.
  +
  +--------------------------------------------------------------+
  | Miscellaneous Enhancements                                   |
  +--------------------------------------------------------------+
  (1) Specification of variable-length subnet masks for passive or
      external routes via RouteD/NCPROUTE ETC.GATEWAYS.
  +
  (2) Automatic clearing of IP routing tables is added for RouteD.
      This eliminates the need to issue an OBEYFILE command to
      clear the IP routing table prior to a RouteD recycle.  Also,
      after a RouteD recycle, old routes added from previous RIP
      updates are cleared to prevent routing problems.
  +
  (3) Added dynamic reconfiguration support for interfaces via
      MODIFY RECONFIG command for RouteD.  Changed interface
      characteristics such as the interface metric, subnet mask,
      and destination address coded in the BSDROUTINGPARMS
      statement of the TCP/IP profile can be dynamically updated
      using this command.
  +
  (4) Added new initialization/modify parameters -svh (-shv) and
      -svhq (-shvq).  In general, the -svh option is equivalent to
      -sv and -hv options combined.  For details on these parms,
      see the section on "Changes to TCP/IP Publications".
  +
  +--------------------------------------------------------------+
  | Installation Instructions                                    |
  +--------------------------------------------------------------+
  (1) Install this PTF on MVS systems to be upgraded for RIP
      Version 2 or variable subnetting support.
  +
  (2) For MVS systems that will not have this PTF installed and
      are running RIPv1 via RouteD, install the following PTFs
      for proper RIP1-RIP2 interactions among the MVS systems:
  +
      UQ03265 (PN88910) for TCPIP V3R1
      UQ03266 (PN88910) for TCPIP V3R2
  +
      See the "Considerations and Restrictions" section for
      information on the RIP1-RIP2 interaction problems.
  +
  (3) Proceed to the next section for configuration instructions.
  +
  +--------------------------------------------------------------+
  | Configuration Instructions                                   |
  +--------------------------------------------------------------+
  (1) To enable variable subnetting in the TCP/IP stack, specify
      VARSUBNETTING option in the ASSORTEDPARMS statement of the
      TCPIP profile.  This option is required if using RouteD for
      RIPv2 support.  Without this option, errors will be
      generated for the unsupported subnet masks.  To disable
      variable subnetting, do not include this option.
  +
  (2) If not using RouteD and variable subnetting is desired for
      static routes, code routes with variable-length subnet masks
      on the GATEWAY statement in the TCPIP profile.  Ensure that
      variable-length subnet masks are not coded for offload
      interfaces due to lack of support.  If defining supernet
      routes, please see the 'Miscellaneous Notes' section.
  +
  (3) If using RouteD and/or NCPROUTE, configure variable-length
      subnet masks, if any, for the local interfaces on the
      BSDROUTINGPARMS statement in TCPIP profile.  Ensure that
      variable-length subnet masks are not coded for offload
      interfaces due to lack of support.
  +
      Apply changes using the RouteD sample files for start proc
      JCL, profile, and ETC.GATEWAYS.  Do the same for NCPROUTE
      if using it.
  +
      Depending upon the network configuration, configure RIP
      control settings via RouteD/NCPROUTE profiles and/or
      ETC.GATEWAYS.  The RIP control settings may be changed
      dynamically via modify command with the PROFILE option.
      If using NCPROUTE without the NCP PTF for RIPv2 and variable
      subnetting support, set the RIP control settings to RIP1.
  +
      If authentication of RIP2 packets is desired on the
      mainframe, specify an authentication key (plain-text
      password) in the RouteD profile for router-wide
      specification.  To enable authentication on a particular
      interface, specify a key in ETC.GATEWAYS for an interface.
      The interface key takes precedence over the router-wide key.
      A blank key dictates that the authentication is disabled at
      the specification level.  Authentication keys can be
      added/removed via modify commands with the PROFILE or
      GATEWAYS options.  Authentication is enabled if keys are
      defined and disabled if they are not.  A blank key indicates
      no authentication.
  +
      Note: For proper RIP2-RIP2 interactions with authentication,
            ensure that keys are identical between routers.
            Otherwise, unauthenticated RIP2 packets are discarded.
  +
  +--------------------------------------------------------------+
  | Miscellaneous Notes                                          |
  +--------------------------------------------------------------+
  (1) To view the contents of incoming or outgoing RIP packets,
      the RouteD parm option of -dp can be used.  This option can
      be enabled dynamically via modify command.   To disable it,
      use the -dq parm.  Example: 'f routed,parms=-dp'
  +
  (2) The subnet masks for routes in the IP routing table can be
      viewed using the NETSTAT GATE command.  For more details on
      routes and interfaces added by RouteD/NCPROUTE, display the
      internal routing and interface tables.   This is
      accomplished by the use of the modify command with the
      TABLES option.  Example: 'f routed,tables'
  +
  (3) If not using RIP and static routing via GATEWAY statement in
      the TCPIP profile is to be used and supernet routes are to
      be defined to reach supernets, special configuration rules
      apply.  The destination address for the supernet must be
      calculated and specified explicitly on the GATEWAY
      statement.  The manual calculation is required due to the
      lack of a bit-contiguous subnet mask specification.  That
      is, the network portion of a subnet mask on the GATEWAY
      statement is zeroes and prevents specification of an
      unnatural network mask.  An unnatural network mask is one
      where the subnet mask is less that the network class mask.
      For example, suppose that networks 193.9.201.0 and
      193.9.200.0 with subnet masks of 255.255.254.0 are to be
      reached via a single supernet route.  The subnet mask
      255.255.254.0 is said to be unnatural because it is less
      than the natural class C network mask of 255.255.255.0.  The
      supernet route is calculated by LOGICALLY ANDing 193.9.201.0
      and 255.255.254.0 together.  Do the same for 193.9.200.0.
      Both network routes yield a supernet route of 193.9.200.0.
      Assume that the gateway address to reach the supernet is
      130.50.10.1 via link TR1.  Then, the GATEWAY statement would
      look like:
  
      Network    FirstHop     Link  PktSize SubnetMask SubnetValue
      193.9.200  130.50.10.1  TR1   2000        0
  +
      The supernet route of 193.9.200 is used to reach both
      networks 193.9.200.0 and 193.9.201.0.
  +
      When defining supernet routes, ensure that adjacent gateways
      and routers support supernetting.  Otherwise, the supernets
      become unreachable.
  +
      If using RIP, the calculations of supernet routes are done
      automatically by the RouteD/NCPROUTE applications.  Again,
      ensure that adjacent routers support supernetting; that is,
      the supernet routes along with unnatural network masks in
      the RIP broadcasts are acceptable by these routers.
  +
  +-------------------------------------------------------------+
  | Changes to TCP/IP Publications                              |
  +-------------------------------------------------------------+
  Refer to INFOAPARs II10398, II10416, II10418, and II10419 for
  description on changes to TCP/IP publications.
  

Problem conclusion

Temporary fix

Comments

• None.
  ×**** PE97/11/06 FIX IN ERROR. SEE APAR PQ09927  FOR DESCRIPTION
  

APAR Information

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

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

  UQ03814

Modules/Macros

• EZAAA00K EZAAB03Y EZAAB07D EZAAB07E EZAAB07F
  EZAAB07G EZAAB07H EZAAB07I EZAAD0YG EZAAD09I EZAAD09J EZAAD09K
  EZAAD09L EZAAD09M EZAAD09N EZAAD09O EZAAD09P EZAAD09Q EZAAD09R
  EZAAI00G EZAAI01I EZAAI011 EZABB02P EZABB02Q EZABB02S EZABB02Y
  EZABB03A EZABB03G EZABB03P EZARTGW  EZARTJCL EZARTMSG EZARTPRF
  EZBNRAF  EZBNRGW  EZBNRIF  EZBNRINP EZBNRMAI EZBNRMSG EZBNRMSN
  EZBNRNCH EZBNRNET EZBNROUT EZBNRPDU EZBNRPRF EZBNRSNP EZBNRSTR
  EZBNRTBL EZBNRTIM EZBNRTRC
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R320 PSY UQ03814

     UP97/05/01 P F704

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.