After the CTIRA_PRIMARY_FALLBACK_INTERVAL elapses, an agent reconnects to its configured primary TEMS if it is available again; but the TCP/IP connection to the socket on the old TEMS also persists.
TCP/IP connection to the socket on the old TEMS also persists. The "netstat -na" command on the Agent will show that it connects to the primary TEMS, and also maintains a connection to the socket on the old TEMS.
Please note: This condition only applies when the TEMS or the Agent is prior to IBM 622 FP6. It was resolved by APAR IZ76410 at ITM 622 FP6 and ITM 623 GA.
Resolving The Problem
Add the "IDLE" parameter to the KDC_FAMILIES environment variable on the agent, it will force idle pipe connections to be closed after some inactivity
interval. IDLE sets (in minutes) the INACTIVITY timer for the associated protocol.
For example, the default:
sets the timer to ZERO, which essentially disables inactivity timing and allows the PIPE connection to persist forever.
On the other hand, the next example:
establishes an inactivity timer for 30 minutes, after which inactive PIPE connections will be disconnected.
As another example, if an Agent is configured for IP:PIPE and IP:SPIPE protocols, the KDC_FAMILIES variable would look similar to this:
KDC_FAMILIES=IP.PIPE PORT:1918 IP:SPIPE PORT 3660 IP use:n
If you want the IP:PIPE connection to terminate after 15 minutes of inactivity, set it to:
KDC_FAMILIES=IP.PIPE IDLE:15 PORT:1918 IP:SPIPE PORT 3660 IP use:n
the IDLE:N is an undocumented variable, please consult IBM support team before using this variable
more detail about CTIRA_PRIMARY_FALLBACK_INTERVAL
24 September 2018