IST1494I
PATH SWITCH status FOR RTP puname TO cpname

Explanation

This message is the first in a group of messages that VTAM® issues in response to an RTP path switch.

  • If status is COMPLETED, the following message group is displayed: 
    IST1494I PATH SWITCH status FOR RTP puname TO cpname
IST1480I RTP END TO END ROUTE - RSCV PATH
IST1460I  TGN    CPNAME            TG TYPE      HPR
IST1461I  tgn    cpname            tgtype       hpr
⋮
IST314I   END
  • If status is FAILED, the following message group is displayed: 
    IST1494I PATH SWITCH status FOR RTP puname TO cpname
IST1495I NO ALTERNATE ROUTE AVAILABLE
IST314I   END
  • If status is OVERRIDDEN, the following message group is displayed: 
    IST1494I PATH SWITCH status FOR RTP puname TO cpname
IST1937I PATH SWITCH REASON: INITIATED BY REMOTE PARTNER
IST314I   END
  • If status is STARTED, the following message group is displayed: 
     IST1494I PATH SWITCH status FOR RTP puname TO cpname 
[IST1817I PATH SWITCH REASON: RTP CONNECTION UNAVAILABLE]
[IST1818I PATH SWITCH REASON: SHORT REQUEST RETRY LIMIT EXHAUSTED]
[IST1819I PATH SWITCH REASON: TG INOP]
[IST1820I PATH SWITCH REASON: MODIFY RTP COMMAND ISSUED]
[IST1821I PATH SWITCH REASON: AUTO PATH SWITCH FOR PSRETRY]
[IST1822I PATH SWITCH REASON: UNKNOWN]
[IST1937I PATH SWITCH REASON: INITIATED BY REMOTE PARTNER]
[IST2239I PATH SWITCH REASON: MNPS ENDPOINT RECOVERY]
[IST2335I PATH SWITCH REASON: XMIT STALL RECOVERY]
 IST314I   END
IST1460I
  • This message is a header message for information displayed in message IST1461I.
IST1461I
  • tgn is the transmission group number.
  • cpname is the destination CP name for the transmission group.
  • tgtype is the transmission group type. The values for tgtype can be one of the following:
    APPN
    Indicates that this TG is an APPN-based TG.
    INTERCHANGE
    Indicates that this TG represents a TG from an interchange node to a subarea node.
    VRTG
    Indicates that this TG is a virtual-route-based TG.
    ISL
    Indicates that this TG is an intersubnet TG.
  • hpr corresponds with the HPR start option. The values for hpr can be:
    RTP
    indicates this VTAM provides RTP-level HPR support
    ANR
    indicates this VTAM provides ANR-level HPR support
    *NA*
    indicates the link to the next node is not HPR capable
    Note: When a link in a particular route is not HPR capable, then the HPR capability for the next node cannot be determined.
IST1480I
  • This message informs the operator that the messages that follow describe the RSCV end-to-end path of the RTP route. The RSCV path represents the route used to send data from the origin CP to the destination CP.
IST1494I
  • status is the outcome of VTAM attempting to do a path switch for this specific RTP.
    COMPLETED
    VTAM was able to complete the path switch for this specific RTP.
    FAILED
    VTAM was not able to complete the path switch for this specific RTP.
    OVERRIDDEN
    VTAM and the partner RTP endpoint have both initiated a path switch for this specific RTP at the same time. The partner RTP endpoint's path switch is accepted by VTAM (this RTP endpoint). This message is issued to indicate the path switch initiated by this RTP endpoint has been overridden by the partner.
    STARTED
    VTAM has begun the path switch for this specific RTP.
  • puname is the RTP PU NAME of the adjacent link station (RTP ALS).
  • cpname is the CP name of the remote partner.
IST1495I
  • No alternate route could be established for the RTP, therefore, no path switch took place. The current RTP remains active.
IST1817I
  • The underlying physical connection or the RTP itself is not in a state suitable for RTP traffic.
IST1818I
  • The RTP partner is not responding to status requests initiated by this RTP endpoint. Each time a status request is sent to the partner a short request timer is set to timeout the transaction. If the short request timer expires and no response is received from the partner, the process is repeated. This process will repeat until the retry limit for the RTP pipe is exhausted. When the retry limit is met, a path switch is requested to try to restore communications with the RTP partner.
  • The short request timer is an internally calculated value. It is based on the observed response time of the RTP pipe. This timer cannot be specified externally.
Tip: HPRPSDLY can be used to add a delay to the path switch when there are network or node constraints with partners. See the HPRPSDLY start option in z/OS Communications Server: SNA Resource Definition Reference.
IST1819I
  • The physical connection that the RTP pipe traverses has suffered an INOP condition.
IST1820I
  • An operator has issued an F RTP command to force an RTP path switch.
IST1821I
  • The PSRETRY start option value is forcing an automatic path switch for this RTP connection.
IST1822I
  • The reason for the RTP path switch is unavailable.
IST1937I
  • The path switch was initiated by the remote partner.
IST2239I
  • The path switch is initiated for the recovery of an MNPS application.
IST2335I
  • The path switch is initiated when a transmission (XMIT) stall recovery is attempted. A transmission stall condition occurs after VTAM retransmits an NLP for the sixth time and at least 10 seconds has elapsed since the NLP was first retransmitted. VTAM attempts recovery by initiating an HPR path switch.

System action

Processing continues.

Operator response

If status is FAILED, save the system log for problem determination and provide the files used for system definition.

System programmer response

Use the output and system definition files provided to assist in determining the cause of the problem. (You might need to work with system programmers in other networks to determine the adjacent SSCP tables used in another network to define the system.)

Routing code

2

Descriptor code

5

Parent topic: IST messages for VTAM network operators IST1200I – IST1599I