Performance system values: Communications configuration recovery

The Communications configuration recovery system value is also known as QCMNRCYLMT. You can use this system value to specify whether to make communications recovery attempts and how many attempts to make.

Quick reference
Location From IBM® Navigator for i, select Configuration and Service > System Values. Right-click on Performance and click Properties, then select the Communications tab.
Special authority None.
Default value Do not attempt to recover.
Changes take effect The next time a communications configuration recovery object is varied on. A change to this system value does not affect a communications configuration object that is already varied on.
Lockable No.

What can I do with this system value?

You can specify whether to attempt to recover from a communications failure. If you select to attempt to recover, you must specify the number of recovery attempts before the system sends messages and the time interval in which the recovery attempts must occur.

Possible values for the number of recovery attempts are 0 through 99. Possible values for the time interval are 0 through 120 minutes.

If the number of recovery attempts is exceeded within the specified time interval, an inquiry message is sent. The inquiry messages go to the configured message queue, which might be the system operator message queue or some other message queue.

If recovery attempts are made but do not exceed the number of recovery attempts within the specified time interval, the count of recovery attempts is reset when the time interval restarts.

If your server is attached to a ROLM computerized branch exchange, the recovery attempts value should never be 0. Recovery attempts are necessary for the server to establish a connection using the ROLM CBX's inbound modem pool.

When you use the Communications configuration recovery system value, consider the following information:

  • If the number of attempts is greater than 0 and the time interval is equal to 0, an infinite number of recovery attempts is made; this is not recommended because of the system resources that may be used and because performance may be affected.
  • If the connection between the iSeries and a personal computer using APPC fails on a local area network (LAN) and the server attempts to recover the connection, unnecessary work is placed on the system.
    Note: If automatic communications error recovery is not used, manual recovery is necessary, which requires operator intervention. A good compromise is to set the automatic recovery limits to just one retry.
    • Use a count limit of 0 and a time interval of more than 0 to turn off second-level error recovery. Turning off second-level recovery may cause the devices and controllers to go into recovery pending (RCYPND) state. A message indicating that an operator intervention is required is sent to QSYSOPR, or the configured message queue. Use manual recovery either to respond to the message in QSYSOPR or the configured message queue, or to vary the objects off and back on.
      Note: First-level error recovery is still done. On a LAN, the Inactivity Timer is used to determine if the remote system is still available. Once the inactivity time expires, first-level error recovery is driven by the LANFRMRTY parameter and the LANRSPTMR parameter.
    • Write applications that can determine if a failure has occurred, and then handle the errors.
      • Monitor the error messages in QSYSOPR, or the configured message queue, when they occur and handle the condition.
      • Monitor the status of the configuration objects by using the Retrieve Configuration Status (QDCRCFGS) and List Configuration Descriptions (QDCLCFGD) application program interfaces (APIs).