Can the keepalive timeouts be configured?
This varies by operating system. There is a program that works on many Unices (though not Linux or Solaris), called netconfig, that allows one to do this and documents many of the variables. It is available by anonymous FTP from cs.ucsd.edu:pub/csl/Netconfig/netconfig2.2.tar.Z In addition, Richard Stevens’ TCP/IP Illustrated, Volume 1 includes a good discussion of setting the most useful variables on many platforms.