[PATCH V2 0/2] Changes in Monitor

[PATCH V2 0/2] Changes in Monitor

[Blazej Kucman]

Hi, Jes, Coly
In first patch blocked is starting monitor when
--scan mode and MD devices list are combiened,
to prevent undefined behaviors.
Second patch containst monitor manual update.

Changes in V2:
- remove unnecessary line from commit message

Blazej Kucman (2):
  Monitor: block if monitor modes are combined.
  Update mdadm Monitor manual.

 Monitor.c  |  7 +++++-
 mdadm.8.in | 71 ++++++++++++++++++++++++++++++++++++++----------------
 2 files changed, 56 insertions(+), 22 deletions(-)

-- 
2.35.3

[PATCH V2 1/2] Monitor: block if monitor modes are combined.

[Blazej Kucman]

Block monitoring start if --scan mode and MD devices list are combined.

Signed-off-by: Blazej Kucman <blazej.kucman@intel.com>
---
 Monitor.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/Monitor.c b/Monitor.c
index 7d7dc4d2..119e17d8 100644
--- a/Monitor.c
+++ b/Monitor.c
@@ -123,7 +123,7 @@ int Monitor(struct mddev_dev *devlist,
 	 *  and if we can get_disk_info and find a name
 	 *  Then we hot-remove and hot-add to the other array
 	 *
-	 * If devlist is NULL, then we can monitor everything because --scan
+	 * If devlist is NULL, then we can monitor everything if --scan
 	 * was given.  We get an initial list from config file and add anything
 	 * that appears in /proc/mdstat
 	 */
@@ -136,6 +136,11 @@ int Monitor(struct mddev_dev *devlist,
 	struct mddev_ident *mdlist;
 	int delay_for_event = c->delay;
 
+	if (devlist && c->scan) {
+		pr_err("Devices list and --scan option cannot be combined - not monitoring.\n");
+		return 1;
+	}
+
 	if (!mailaddr)
 		mailaddr = conf_get_mailaddr();
 
-- 
2.35.3

[PATCH V2 2/2] Update mdadm Monitor manual.

[Blazej Kucman]

- describe monitor work modes,
- clarify the turning off condition,
- describe the mdmonitor.service as a prefered management way.

Signed-off-by: Blazej Kucman <blazej.kucman@intel.com>
---
 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:
 
-- 
2.35.3

Re: [PATCH V2 0/2] Changes in Monitor

[Jes Sorensen]

On 12/19/22 05:21, Blazej Kucman wrote:
> Hi, Jes, Coly
> In first patch blocked is starting monitor when
> --scan mode and MD devices list are combiened,
> to prevent undefined behaviors.
> Second patch containst monitor manual update.
> 
> Changes in V2:
> - remove unnecessary line from commit message
> 
> Blazej Kucman (2):
>   Monitor: block if monitor modes are combined.
>   Update mdadm Monitor manual.
> 
>  Monitor.c  |  7 +++++-
>  mdadm.8.in | 71 ++++++++++++++++++++++++++++++++++++++----------------
>  2 files changed, 56 insertions(+), 22 deletions(-)
> 

Applied,

Thanks,
Jes