WCCILdata/WCCILevent - SYS/SEVERE - Alive timeout expired, closing connection to "manager-ID"

The following log message can be displayed during the runtime of the project. The log message is written to the PVSS_II.log-file.

WCCILevent (0), 2012.05.22 08:48:45.436, SYS, SEVERE, 39, Connection lost, Alive timeout expired, closing connection to (SYS: 1 Ui -num 2 CONN: 1) (P) @ CLIENT1 (192.168.178.188).
Last message expected at 2012.05.22 08:48:45.430.

The log message with symbolic names:

WCCILevent (0), <TIMESTAMP>, SYS, SEVERE, 39, Connection lost, Alive timeout expired, closing connection to (<manager-ID>) (P) @ <hostname> (<IP-address>). Last message
expected at <alive-timeout>

The log message describes that the data-/event-manager has closed the connection to the process (<manager-ID>) started on the computer (<hostname> ) due to the fact that no alive message was received within the given alive-timeout.

The timeout can be reached due to a network error or when the process on the other computer <hostname> was stopped.

For additional information see the PVSS_II.log-file on the other computer.

Note:

The alive timeout can be specified with the config entry aliveTimeout(default-value 10 seconds). The given timespan is divided by 10 to get the interval for sending alive-messages.

Specify the alive-thread a higher process-priority by using the config entry alivePriorityClass .

The problem can also be solved by increasing the aliveTimeout-setting.

  • If the problem occurs several times, check the network and the network bandwith.

This problem can also occur during a time synchronization. If the time is set back or forth, the timespan to receive an alive message might be exceeded.

Example for aliveTimeout = 10 and setting the time forth:

-- time when the last alive message was received: 2012.06.04 14:51:30
therefore the time to receive at least one alive-message is 2012.06.04 14:51:40
-- time is set to 2012.06.04 14:51:50 by the time synchronization

An aliveTimeout is detected.

Example for aliveTimeout = 10 and setting the time back:

-- time when the last alive message was sent: 2012.06.04 14:51:30
therefore the time to send the next alive-message is 2012.06.04 14:51:31
-- time is set to 2012.06.04 14:51:10 by the time synchronization

It will take 21 seconds until the next alive message is sent and therefore the server (data/event) will detect an alive timeout.