xref: /freebsd/sys/contrib/openzfs/cmd/zed/zed.d/deadman-slot_off.sh (revision aca928a50a42f00f344df934005b09dbcb4e2f77)
1#!/bin/sh
2# shellcheck disable=SC3014,SC2154,SC2086,SC2034
3#
4# Turn off disk's enclosure slot if an I/O is hung triggering the deadman.
5#
6# It's possible for outstanding I/O to a misbehaving SCSI disk to neither
7# promptly complete or return an error.  This can occur due to retry and
8# recovery actions taken by the SCSI layer, driver, or disk.  When it occurs
9# the pool will be unresponsive even though there may be sufficient redundancy
10# configured to proceeded without this single disk.
11#
12# When a hung I/O is detected by the kmods it will be posted as a deadman
13# event.  By default an I/O is considered to be hung after 5 minutes.  This
14# value can be changed with the zfs_deadman_ziotime_ms module parameter.
15# If ZED_POWER_OFF_ENCLOSURE_SLOT_ON_DEADMAN is set the disk's enclosure
16# slot will be powered off causing the outstanding I/O to fail.  The ZED
17# will then handle this like a normal disk failure and FAULT the vdev.
18#
19# We assume the user will be responsible for turning the slot back on
20# after replacing the disk.
21#
22# Note that this script requires that your enclosure be supported by the
23# Linux SCSI Enclosure services (SES) driver.  The script will do nothing
24# if you have no enclosure, or if your enclosure isn't supported.
25#
26# Exit codes:
27#   0: slot successfully powered off
28#   1: enclosure not available
29#   2: ZED_POWER_OFF_ENCLOSURE_SLOT_ON_DEADMAN disabled
30#   3: System not configured to wait on deadman
31#   4: The enclosure sysfs path passed from ZFS does not exist
32#   5: Enclosure slot didn't actually turn off after we told it to
33
34[ -f "${ZED_ZEDLET_DIR}/zed.rc" ] && . "${ZED_ZEDLET_DIR}/zed.rc"
35. "${ZED_ZEDLET_DIR}/zed-functions.sh"
36
37if [ ! -d /sys/class/enclosure ] ; then
38	# No JBOD enclosure or NVMe slots
39	exit 1
40fi
41
42if [ "${ZED_POWER_OFF_ENCLOSURE_SLOT_ON_DEADMAN}" != "1" ] ; then
43	exit 2
44fi
45
46if [ "$ZEVENT_POOL_FAILMODE" != "wait" ] ; then
47	exit 3
48fi
49
50if [ ! -f "$ZEVENT_VDEV_ENC_SYSFS_PATH/power_status" ] ; then
51	exit 4
52fi
53
54# Turn off the slot and wait for sysfs to report that the slot is off.
55# It can take ~400ms on some enclosures and multiple retries may be needed.
56for i in $(seq 1 20) ; do
57	echo "off" | tee "$ZEVENT_VDEV_ENC_SYSFS_PATH/power_status"
58
59	for j in $(seq 1 5) ; do
60		if [ "$(cat $ZEVENT_VDEV_ENC_SYSFS_PATH/power_status)" == "off" ] ; then
61			break 2
62		fi
63		sleep 0.1
64	done
65done
66
67if [ "$(cat $ZEVENT_VDEV_ENC_SYSFS_PATH/power_status)" != "off" ] ; then
68	exit 5
69fi
70
71zed_log_msg "powered down slot $ZEVENT_VDEV_ENC_SYSFS_PATH for $ZEVENT_VDEV_PATH"
72