The default KeepAlive behavior is controlled by the following NW TCPIP OPTION values:
-
KEEPALIVEINTERVAL (KAI)
-
DIALOGBLOCKEDTIMEOUT (DBT)
Valid values for these commands range from 0 through 1440 minutes. The default value is 0 minutes. When KAI is set to 0, keep alive is disabled by default. When DBT is set to 0, connections do not time out due to inactivity.
| Note: | The new KAI and DBT intervals are immediately applied to all active connections using the default values. Active or idle activity is not examined or acted on until the new KeepAlive interval has expired. |
The keep alive options are described as follows.
|
Keep Alive Option |
Description |
|---|---|
|
KeepAliveInterval (KAI) |
The KeepAliveInterval (KAI) is the duration of a KeepAlive interval in minutes. If no traffic is detected during the previous interval, a keep alive message is sent. A positive response to a keep alive message is considered traffic. On a healthy but otherwise silent connection, a keep alive message is sent at the end of every other interval. The default value is used when the application has not specified a value (refer to “DIALOGCHECKINTERVAL” in the File Attributes Programming Reference Manual and “SO_KeepAlive” in the MCP Sockets Service Programming Guide for more information.) A value of 0 indicates that activity monitoring is not performed and no keep alive packets are issued. Data Type <integer> Range 0 through 1440 minutes Default = 0 minutes |
|
DialogBlockedTimeout (DBT) |
The DialogBlockedTimeout (DBT) specifies the default period of inactivity by a dialog after which the connection will be closed. The Blocked Timeout period begins after the first KeepAlive interval expires. If no subsequent activity occurs during the period, the connection is closed. For port file based applications, the state of the port subfile is changed to Blocked when the period begins. If activity resumes during this period, the port subfile is restored to OPEN. The default value is used when the application has not specified a value (refer to “BLOCKEDTIMEOUT” in the File Attributes Programming Reference Manual and “SO_KeepAlive” in the MCP Sockets Service Programming Guide for more information.) A value of 0 indicates that dialogs are not closed due to inactivity. Note that this period depends on a value of KeepAliveInterval that is not 0. Data Type <integer> Range 0 through 1440 minutes Default = 0 minutes |
