From 725e37cd14866906ba28c970394b9f7a4cd97413 Mon Sep 17 00:00:00 2001 From: Blazej Kucman Date: Mon, 19 Dec 2022 11:21:58 +0100 Subject: [PATCH 64/83] Update mdadm Monitor manual. - describe monitor work modes, - clarify the turning off condition, - describe the mdmonitor.service as a prefered management way. Signed-off-by: Blazej Kucman Signed-off-by: Jes Sorensen --- mdadm.8.in | 71 ++++++++++++++++++++++++++++++++++++++---------------- 1 file changed, 50 insertions(+), 21 deletions(-) diff --git a/mdadm.8.in b/mdadm.8.in index 70c79d1e..64f71ed1 100644 --- a/mdadm.8.in +++ b/mdadm.8.in @@ -2548,13 +2548,33 @@ Usage: .I options... devices... .PP -This usage causes +Monitor option can work in two modes: +.IP \(bu 4 +system wide mode, follow all md devices based on +.B /proc/mdstat, +.IP \(bu 4 +follow only specified MD devices in command line. +.PP + +.B \-\-scan - +indicates system wide mode. Option causes the +.I monitor +to track all md devices that appear in +.B /proc/mdstat. +If it is not set, then at least one +.B device +must be specified. + +Monitor usage causes .I mdadm to periodically poll a number of md arrays and to report on any events noticed. -.I mdadm -will never exit once it decides that there are arrays to be checked, -so it should normally be run in the background. + +In both modes, +.I monitor +will work as long as there is an active array with redundancy and it is defined to follow (for +.B \-\-scan +every array is followed). As well as reporting events, .I mdadm @@ -2565,15 +2585,6 @@ or .B domain and if the destination array has a failed drive but no spares. -If any devices are listed on the command line, -.I mdadm -will only monitor those devices, otherwise, all arrays listed in the -configuration file will be monitored. Further, if -.B \-\-scan -is given, then any other md devices that appear in -.B /proc/mdstat -will also be monitored. - The result of monitoring the arrays is the generation of events. These events are passed to a separate program (if specified) and may be mailed to a given E-mail address. @@ -2586,16 +2597,34 @@ device if relevant (such as a component device that has failed). If .B \-\-scan -is given, then a program or an E-mail address must be specified on the -command line or in the config file. If neither are available, then +is given, then a +.B program +or an +.B e-mail +address must be specified on the +command line or in the config file. If neither are available, then .I mdadm will not monitor anything. -Without -.B \-\-scan, -.I mdadm -will continue monitoring as long as something was found to monitor. If -no program or email is given, then each event is reported to -.BR stdout . +For devices given directly in command line, without +.B program +or +.B email +specified, each event is reported to +.BR stdout. + +Note: For systems where +.If mdadm monitor +is configured via systemd, +.B mdmonitor(mdmonitor.service) +should be configured. The service is designed to be primary solution for array monitoring, +it is configured to work in system wide mode. +It is automatically started and stopped according to current state and types of MD arrays in system. +The service may require additional configuration, like +.B e-mail +or +.B delay. +That should be done in +.B mdadm.conf. The different events are: -- 2.38.1