udev-md-raid-safe-timeouts.rules

# Copyright (C) 2017 by Jonathan G. Underwood
# This file is part of mdraid-safe-timeouts.
#
# mdraid-safe-timeouts 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 3 of
# the License, or (at your option) any later version.
#
# Foobar is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with mdraid-safe-timeouts.  If not, see
# <https://www.gnu.org/licenses/>.

# This file causes block devices with Linux RAID (mdadm) signatures to
# attempt to set safe timeouts for the drives involved
# See udev(8) for syntax

# Don't process any events if anaconda is running as anaconda brings up
# raid devices manually
ENV{ANACONDA}=="?*", GOTO="md_timeouts_end"

SUBSYSTEM!="block|machinecheck", GOTO="md_timeouts_end"

# "noiswmd" on kernel command line stops mdadm from handling
# "isw" (aka IMSM - Intel RAID).
# "nodmraid" on kernel command line stops mdadm from handling
# "isw" or "ddf".
IMPORT{cmdline}="nodmraid"
ENV{nodmraid}=="?*", GOTO="md_timeouts_end"
IMPORT{cmdline}="noiswmd"
ENV{noiswmd}=="?*", GOTO="md_timeouts_end"

# Set controller timeout for parent disk of each partition if the
# partition is a mdraid partition of higher than raid 0, and the disk
# doesn't have scterc turned on (i.e. if it's disabled or the disk
# doesn't support it). We determine if the disk has SCTERC turned on
# by examining the output of smartctl and seeing if it contains the
# word "seconds". If the word "seconds" is found we take this to imply
# STCERC is turned on, and take no action. Otherwise we set the drive
# controller timeout to 180 seconds. It would be better to check the
# exit status code of smartctl rather than grepping for "seconds", but
# it's not clear what that will be in the three cases (supported and
# turned on, supported but disabled, not supported).

ENV{DEVTYPE}!="partition", GOTO="md_timeouts_end"

IMPORT{program}="/sbin/mdadm --examine --export $devnode"

ACTION=="add|change", \
  ENV{ID_FS_TYPE}=="linux_raid_member", \
  ENV{MD_LEVEL}=="raid[1-9]*", \
  TEST=="/sys/block/$parent/device/timeout", \
  TEST=="/usr/sbin/smartctl", \
  PROGRAM!="/bin/sh -c '/usr/sbin/smartctl -l scterc /dev/$parent | grep -q seconds && exit 0 || exit 1'", \
  RUN+="/bin/sh -c 'echo 180 > /sys/block/$parent/device/timeout && /usr/bin/logger timeout for /dev/$parent set to 180 secs'"

LABEL="md_timeouts_end"