From 68b356a1b47e201881c61bd4abfacf9a53a4534f Mon Sep 17 00:00:00 2001 From: Dan Fandrich Date: Wed, 9 Mar 2022 22:11:13 -0800 Subject: [PATCH] keepalive-time.d: It takes many probes to detect brokenness --- docs/cmdline-opts/keepalive-time.d | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/docs/cmdline-opts/keepalive-time.d b/docs/cmdline-opts/keepalive-time.d index cdc150aa79..4bd675033c 100644 --- a/docs/cmdline-opts/keepalive-time.d +++ b/docs/cmdline-opts/keepalive-time.d @@ -9,8 +9,11 @@ See-also: no-keepalive max-time This option sets the time a connection needs to remain idle before sending keepalive probes and the time between individual keepalive probes. It is currently effective on operating systems offering the TCP_KEEPIDLE and -TCP_KEEPINTVL socket options (meaning Linux, recent AIX, HP-UX and more). This -option has no effect if --no-keepalive is used. +TCP_KEEPINTVL socket options (meaning Linux, recent AIX, HP-UX and more). +Keepalives are used by the TCP stack to detect broken networks on idle +connections. The number of missed keepalive probes before declaring the +connection down is OS dependent and is commonly 9 or 10. This option has no +effect if --no-keepalive is used. If this option is used several times, the last one will be used. If unspecified, the option defaults to 60 seconds. -- 2.47.3