MAX_INCOMPLETE_CONNECTIONS

onconfig.std value

1024

units

Number of listener threads

takes effect

When the database server is stopped and restarted

utilities

onmode -wf
onmode-wm

refer to

The Security chapter in the IBM Informix Administrator's Guide

Use MAX_INCOMPLETE_CONNECTIONS to specify the maximum number of incomplete connections in a session. After this number is reached, an error message is written in the online message log stating that the server might be under a Denial of Service attack. See also information about the LISTEN_TIMEOUT configuration parameter on page LISTEN_TIMEOUT.

Depending on the machine capability of holding the threads (in number), you can configure MAX_INCOMPLETE_CONNECTIONS to a higher value and depending on the network traffic, you can set LISTEN_TIMEOUT to a lower value to reduce the chance that an attack can reach the maximum limit.

Both the MAX_INCOMPLETE_CONNECTIONS and the LISTEN_TIMEOUT configuration parameters can be changed using the onmode -wf option or superseded for a session with the onmode -wm option. For more information about onmode, see Dynamically Change Certain Connection, PDQ, and Memory Parameters.