I am running some program that connect from 192.168.0.2 to 192.168.0.1 through the port 1186 , but in the host 192.168.0.1 found that the port 1186 is occupied by 192.168.0.2 ( there are three sessions ) , now host 192.168.0.1 can't connect one more session , it may be because the max. limit of session is full , can suggest how to erase this "CLOSE_WAIT" connection at 192.168.0.1 ? thx.



At 192.168.0.1

# netstat -na |grep 1186
tcp 0 0 0.0.0.0:1186 0.0.0.0:* LISTEN
tcp 1 0 192.168.0.1:1186 192.168.0.2:32783 CLOSE_WAIT
tcp 1 0 192.168.0.1:1186 192.168.0.2:32776 CLOSE_WAIT
tcp 1 0 192.168.0.1:1186 192.168.0.2:32787 CLOSE_WAIT

IIRC the kernel actually holds connections open after the connections close for some reason (there is a reason for it, but I can't remember off the top of my head). One way to get around it is use setsockopt(2) in your program and set the SO_REUSEADDR option on the socket. Otherwise maybe there's a sysctl that controls this, but looking through them I didn't see anything offhand.