每次重启后，mdadm 都会检查 RAID 5 阵列

Question

更新日期：2021/06/18

对于 mdcheck_start.timer mdcheck_continue.timer 中的 svc；执行 sudo systemctl stop ${svc}；sudo systemctl disable ${svc}；完成

取自： https://a20.net/bert/2020/11/02/disable-periodic-raid-check-on-ubuntu-20-04-systemd/

更新 04/05/2021 开始。
我之前的回答似乎没有帮助。
尽管发生了变化，但检查再次发生/etc/default/mdadm。

我发现了其他一些需要调查的东西。
mdcheck_start.service
mdcheck_start.timer
mdcheck_continue.service
mdcheck_continue.timer
/etc/systemd/system/mdmonitor.service.wants/mdcheck_start.timer
/etc/systemd/system/mdmonitor.service.wants/mdcheck_continue.timer
/etc/systemd/system/mdmonitor.service.wants/mdmonitor-oneshot.timer

systemctl status mdcheck_start.service
● mdcheck_start.service - MD array scrubbing
     Loaded: loaded (/lib/systemd/system/mdcheck_start.service; static; vendor preset: enabled)
     Active: inactive (dead)
TriggeredBy: ● mdcheck_start.timer

systemctl status mdcheck_start.timer
● mdcheck_start.timer - MD array scrubbing
     Loaded: loaded (/lib/systemd/system/mdcheck_start.timer; enabled; vendor preset: enabled)
     Active: active (waiting) since Sun 2021-05-02 19:40:50 CEST; 1 day 14h ago
    Trigger: Sun 2021-06-06 22:36:42 CEST; 1 months 3 days left
   Triggers: ● mdcheck_start.service

May 02 19:40:50 xxx systemd[1]: Started MD array scrubbing.

systemctl status mdcheck_continue.service
● mdcheck_continue.service - MD array scrubbing - continuation
     Loaded: loaded (/lib/systemd/system/mdcheck_continue.service; static; vendor preset: enabled)
     Active: inactive (dead)
TriggeredBy: ● mdcheck_continue.timer
  Condition: start condition failed at Tue 2021-05-04 06:38:39 CEST; 3h 26min ago
             └─ ConditionPathExistsGlob=/var/lib/mdcheck/MD_UUID_* was not met

systemctl status mdcheck_continue.timer
● mdcheck_continue.timer - MD array scrubbing - continuation
     Loaded: loaded (/lib/systemd/system/mdcheck_continue.timer; enabled; vendor preset: enabled)
     Active: active (waiting) since Sun 2021-05-02 19:40:50 CEST; 1 day 14h ago
    Trigger: Wed 2021-05-05 00:35:53 CEST; 14h left
   Triggers: ● mdcheck_continue.service

May 02 19:40:50 xxx systemd[1]: Started MD array scrubbing - continuation.

sudo cat /etc/systemd/system/mdmonitor.service.wants/mdcheck_start.timer
#  This file is part of mdadm.
#
#  mdadm is free software; you can redistribute it and/or modify it
#  under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.

[Unit]
Description=MD array scrubbing

[Timer]
OnCalendar=Sun *-*-1..7 1:00:00
RandomizedDelaySec=24h
Persistent=true

[Install]
WantedBy=mdmonitor.service
Also=mdcheck_continue.timer

sudo cat /etc/systemd/system/mdmonitor.service.wants/mdcheck_continue.timer 
#  This file is part of mdadm.
#
#  mdadm is free software; you can redistribute it and/or modify it
#  under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.

[Unit]
Description=MD array scrubbing - continuation

[Timer]
OnCalendar=daily
RandomizedDelaySec=12h
Persistent=true

[Install]
WantedBy=mdmonitor.service

sudo cat /etc/systemd/system/mdmonitor.service.wants/mdmonitor-oneshot.timer 
#  This file is part of mdadm.
#
#  mdadm is free software; you can redistribute it and/or modify it
#  under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.

[Unit]
Description=Reminder for degraded MD arrays

[Timer]
OnCalendar=daily
RandomizedDelaySec=24h
Persistent=true

[Install]
WantedBy= mdmonitor.service

更新 2021 年 4 月 5 日结束。

尝试sudo dpkg-reconfigure mdadm。

请注意，我不确定上述提示是否有帮助。
我在 20.04 上的 raid5 也遇到了同样的问题。

首先，我尝试/etc/default/mdadm手动编辑并更改AUTOCHECK=true为AUTOCHECK=false。但这没有帮助。

今天我使用了dpkg-reconfigure mdadm。现在/etc/default/mdadm文件看起来一样了（AUTOCHECK=false），但作为其中的一部分，dpkg-reconfigure mdadm还有一个update-initramfs调用。希望这会有所帮助。

... update-initramfs: deferring update (trigger activated) ...

扩展日志：

sudo dpkg-reconfigure mdadm
update-initramfs: deferring update (trigger activated)
Sourcing file `/etc/default/grub'
Sourcing file `/etc/default/grub.d/50-curtin-settings.cfg'
Sourcing file `/etc/default/grub.d/init-select.cfg'
Generating grub configuration file ...
File descriptor 3 (pipe:[897059]) leaked on vgs invocation. Parent PID 655310: /usr/sbin/grub-probe
File descriptor 3 (pipe:[897059]) leaked on vgs invocation. Parent PID 655310: /usr/sbin/grub-probe
Found linux image: /boot/vmlinuz-5.4.0-72-generic
Found initrd image: /boot/initrd.img-5.4.0-72-generic
Found linux image: /boot/vmlinuz-5.4.0-71-generic
Found initrd image: /boot/initrd.img-5.4.0-71-generic
Found linux image: /boot/vmlinuz-5.4.0-70-generic
Found initrd image: /boot/initrd.img-5.4.0-70-generic
File descriptor 3 (pipe:[897059]) leaked on vgs invocation. Parent PID 655841: /usr/sbin/grub-probe
File descriptor 3 (pipe:[897059]) leaked on vgs invocation. Parent PID 655841: /usr/sbin/grub-probe
done
Processing triggers for initramfs-tools (0.136ubuntu6.4) ...
update-initramfs: Generating /boot/initrd.img-5.4.0-72-generic

完整/etc/default/mdadm文件：

cat /etc/default/mdadm 
# mdadm Debian configuration
#
# You can run 'dpkg-reconfigure mdadm' to modify the values in this file, if
# you want. You can also change the values here and changes will be preserved.
# Do note that only the values are preserved; the rest of the file is
# rewritten.
#

# AUTOCHECK:
#   should mdadm run periodic redundancy checks over your arrays? See
#   /etc/cron.d/mdadm.
AUTOCHECK=false

# AUTOSCAN:
#   should mdadm check once a day for degraded arrays? See
#   /etc/cron.daily/mdadm.
AUTOSCAN=true

# START_DAEMON:
#   should mdadm start the MD monitoring daemon during boot?
START_DAEMON=true

# DAEMON_OPTIONS:
#   additional options to pass to the daemon.
DAEMON_OPTIONS="--syslog"

# VERBOSE:
#   if this variable is set to true, mdadm will be a little more verbose e.g.
#   when creating the initramfs.
VERBOSE=false

Answer 1