From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Benjamin Marzinski Date: Tue, 15 Dec 2020 12:47:14 -0600 Subject: [PATCH] multipath.conf.5: Improve checker_timeout description I was asked to explain how checker_timeout works for checkers like directio, that don't issue scsi commands with an explicit timeout Signed-off-by: Benjamin Marzinski --- multipath/multipath.conf.5 | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/multipath/multipath.conf.5 b/multipath/multipath.conf.5 index 60954574..a5686090 100644 --- a/multipath/multipath.conf.5 +++ b/multipath/multipath.conf.5 @@ -634,8 +634,13 @@ The default is: \fBno\fR . .TP .B checker_timeout -Specify the timeout to use for path checkers and prioritizers that issue SCSI -commands with an explicit timeout, in seconds. +Specify the timeout to use for path checkers and prioritizers, in seconds. +Only prioritizers that issue scsi commands use checker_timeout. Checkers +that support an asynchronous mode (\fItur\fR and \fIdirectio\fR), will +return shortly after being called by multipathd, regardless of whether the +storage array responds. If the storage array hasn't responded, mulitpathd will +check for a response every second, until \fIchecker_timeout\fR seconds have +elapsed. .RS .TP The default is: in \fB/sys/block/sd/device/timeout\fR -- 2.17.2