What exactly does SO_KEEPALIVE do?
Answer / chaitanya
The SO_KEEPALIVE option causes a packet (called a 'keepalive probe') to be sent to the remote system if a long time (by default, more than 2 hours) passes with no other data being sent or received. This packet is designed to provoke an ACK response from the peer. This enables detection of a peer which has become unreachable (e.g. powered off or disconnected from the net).
Note that the figure of 2 hours comes from RFC1122, "Requirements for Internet Hosts". The precise value should be configurable, but I've often found this to be difficult. The only implementation I know of that allows the keepalive interval to be set per-connection is SVR4.2.
Is This Answer Correct ? | 0 Yes | 0 No |
Why does connect() succeed even before my server did an accept()?
Is tcp or unix socket faster?
What is a socket connection?
Are unix sockets faster than tcp?
Why does it take so long to detect that the peer died?
What exactly does SO_KEEPALIVE do?
What is the difference between a socket and a port?
How do unix sockets work?
Is a socket a file?
How would I put my socket in non-blocking mode?
How often should I re-transmit un-acknowleged messages?
What is the difference between read() and recv()?