ASA Database Administration Guide
Set the period at which to send liveness packets.
{ dbsrv9 | dbeng9 } -tl seconds ...
All database servers using TCP/IP or SPX.
A liveness packet is sent periodically across a client/server TCP/IP or SPX communications protocol to confirm that a connection is intact. If the server runs for a LivenessTimeout period (default 2 minutes) without detecting a liveness packet on a connection, the communication is severed, and the server drops the connection associated with that client. UNIX non-threaded clients and TDS connections do not do liveness checking.
The -tl option on the server sets the LivenessTimeout value for all clients that do not specify a liveness period.
Liveness packets are sent when a connection has not sent any packets for between one third and two thirds of the LivenessTimeout value.
When there are more than 200 connections, the server automatically calculates a higher LivenessTimeout value based on the stated LivenessTimeout value. This enables the server to handle a large number of connections more efficiently. Liveness packets are sent between one third and two thirds of the LivenessTimeout on each idle connection. Large numbers of liveness packets are not sent at the same time. If liveness packets take a long time to send (depending on the network, the machine's hardware, and the CPU and network load on the machine), it is possible that liveness packets will sent after two thirds of the LivenessTimeout. A warning appears in the server console if the liveness sends take a long time. If this warning occurs, consider increasing the LivenessTimeout value.
Although it is not generally recommended, you can disable liveness by specifying the following:
dbsrv9 -tl 0
Rather than disabling the LivenessTimeout option, consider increasing the value to 1 hour as follows:
dbsrv9 -tl 3600
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