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IV45924: HPR HANG DUE TO HOST GAP MESSAGE PACKET BEING DROPPED IN THE NETWORK

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • A remote VTAM host has fixed pacing window size of 1.  As the
    VTAM attempts to send data which needs more than 1 RU to
    complete it requests another pacing window to complete its
    transfer with a pacing indicator.  CS/AIX sends an IPR with a
    status request (SR) with RASAP set.  The remote VTAM host
    responds with a status with the Received Sequence Number (RSN)
    set to our BSN before the IPR, indicating that the remote host
    never received the IPR.  However, the session continues to hang
    as CS/AIX never attempts to retransmit the IPR packet.
    

Local fix

Problem summary

  • USERS AFFECTED:
    All users of HPR
    
    PROBLEM SUMMARY:
    Directly connected HPR/IP connection can hang up if packets are
    lost in both directions in quick succession and there is no
    other activity on the connection to drive retries. The gap
    detected packet from the mainframe was dropped in the network.
    

Problem conclusion

  • Code has been changed to restart the short request timer when a
    status packet is received which has an implicit gap detected,
    i.e. the partner system indicates that it has not seen the last
    system sequence number transmitted but has not reported the gap
    detected yet (it is waiting for the refifo timer to expire).
    

Temporary fix

  • sna_v5router64
    

Comments

APAR Information

  • APAR number

    IV45924

  • Reported component name

    CS AIX V6.X

  • Reported component ID

    5765E5100

  • Reported release

    631

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2013-07-22

  • Closed date

    2013-07-22

  • Last modified date

    2013-09-18

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

    IV41297

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

Fix information

  • Fixed component name

    CS AIX V6.X

  • Fixed component ID

    5765E5100

Applicable component levels

  • R631 PSY U860529

       UP13/09/18 I 1000

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Document Information

Modified date:
03 October 2021