Re: sysctl_tcp_keepalive_time

On 16/08/07, Simon Peter <simon.peter@xxxxxx> wrote:
Hi,

is there any reason why sysctl_tcp_keepalive_time (reflected
by /proc/sys/net/ipv4/tcp_keepalive_time) is set to 7200 seconds? Is
this specified somewhere?

RFC 1122, section 4.2.3.6 - http://www.faqs.org/rfcs/rfc1122.html

"
4.2.3.6 TCP Keep-Alives

Implementors MAY include "keep-alives" in their TCP
implementations, although this practice is not universally
accepted. If keep-alives are included, the application MUST
be able to turn them on or off for each TCP connection, and
they MUST default to off.

Keep-alive packets MUST only be sent when no data or
acknowledgement packets have been received for the
connection within an interval. This interval MUST be
configurable and MUST default to no less than two hours.
"

This page may also be of interrest to you :
http://www.uic.rsu.ru/doc/inet/tcp_stevens/tcp_keep.htm

Also see "man 7 tcp"


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Jesper Juhl <jesper.juhl@xxxxxxxxx>
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