Re: Determining which spindle is out of order

[Phil Turmel <philip@turmel.org>]

On 11/06/2010 06:22 AM, Leslie Rhorer wrote:
> 
> 
>> -----Original Message-----
>> From: linux-raid-owner@vger.kernel.org [mailto:linux-raid-
>> owner@vger.kernel.org] On Behalf Of Phil Turmel
>> Sent: Wednesday, November 03, 2010 4:55 PM
>> To: Nat Makarevitch
>> Cc: linux-raid@vger.kernel.org
>> Subject: Re: Determining which spindle is out of order
>>
>> On 11/3/2010 2:13 PM, Nat Makarevitch wrote:
>>> Hi,
>>>
>>> After a spindle (physical hard disk, a "drive") failure in a "md" RAID
>> array,
>>> how can we know which spindle must be replaced?
>>>
>>> We want to avoid extracting a working spindle by mistakenly thinking it
>> is the
>>> faulty one...
>>
>> I wrote a little script that would tell me device name and serial number
>> for each host port on my motherboard, along with anything else that lists
>> a scsi host in sysfs.  Output like so:
>>
>> Controller device @ pci0000:00/0000:00:1c.1/0000:06:00.0 [ahci]
>>   RAID bus controller: Marvell Technology Group Ltd. 88SE6145 SATA II PCI-
>> E controller (rev a1)
>>     host4: [Empty]
>>     host5: /dev/sdd ATA WDC WD5000AAKS-7 {SN: WD-WMAWF1370668}
>>     host6: [Empty]
>>     host7: [Empty]
>>     host8: [Empty]
>> Controller device @ pci0000:00/0000:00:1f.1 [ata_piix]
>>   IDE interface: Intel Corporation 82801G (ICH7 Family) IDE Controller
>> (rev 01)
>>     host9: [Empty]
>>     host10: [Empty]
>> Controller device @ pci0000:00/0000:00:1f.2 [ahci]
>>   SATA controller: Intel Corporation 82801GR/GH (ICH7 Family) SATA AHCI
>> Controller (rev 01)
>>     host0: /dev/sda ATA ST31000333AS {SN: 9TE1LTW0}
>>     host1: /dev/sdb ATA ST31000333AS {SN: 9TE1MAJT}
>>     host2: /dev/sdc ATA ST31000333AS {SN: 9TE1MV1R}
>>     host3: /dev/sr0 HL-DT-ST BD-RE GBW-H20L
>>
>> Shows me my empty ports, too.  As long as I keep my cables straight to my
>> hot-swap bays, getting the right drive is a snap.
> 
> 	I haven't had a chance to dig into the script, but it doesn't
> produce any output when I run it on one of my servers, and on the other one
> it produces errors on line 7, but otherwise seems to work.
> 

Thanks for the feedback.  The script only looks in sysfs for controllers
implementing the scsi_host interface.  So it won't pick up anything using
the legacy IDE interface.  If that's not the case on the first server, I'd
like to see lspci -vvv for the controller in question.

As for the errors on line #7, that's likely to be the whitespace problem that
Roman pointed out.  Based on his comment, I've adjusted the script to be more
robust (a little faster, too).  Please give it a try:

#! /bin/bash
#
# Examine specific system host devices to identify the drives attached
#

function describe_controller () {
	unset SUBSYSTEM PCI_ID DEVICE PCI_SLOT_NAME Manufacturer Product Serial
	eval `udevadm info --query=all --path="$1" | \
		sed -rn -e 's/^E: (\w+)=(.+)$/\1="\2"/;T;p'`
	echo "Controller device @ ${1##/sys/devices/} [$DRIVER]"
	if [[ -n "$PCI_SLOT_NAME" ]] ; then
		echo -e "  `lspci -s $PCI_SLOT_NAME |cut -d\  -f2-`"
		return
	fi
	if [[ "${MODALIAS:0:4}" == "usb:" ]] ; then
		eval `lsusb -D ${DEVICE/proc/dev/} | \
			sed -rn -e 's% *i(Manufacturer|Product|Serial) +[0-9]+ +(.+) *$%\1="\2"%;T;p'`
		echo -e "  [$Manufacturer] $Product {SN: $Serial}"
		return
	fi
	echo -e "  $SUBSYSTEM $MODALIAS"
}

function describe_device () {
	targ=${1%/block/*}
	vnd="`cat $targ/vendor`"
	mdl=`cat $targ/model`
	rdev=`readlink -f "$1"`
	if [[ -d $rdev ]] ; then
		bdev="`basename $rdev`"
		sn="`sginfo -s /dev/$bdev | \
			sed -rn -e \"/Serial Number/{s%^.+' *(.+) *'.*\\\$%\\\\1%;p;q}\"`" &>/dev/null
		if [[ -n "$sn" ]] ; then
			echo -e "    $bhost: `echo /dev/$bdev $vnd $mdl {SN: $sn}`"
		else
			echo -e "    $bhost: `echo /dev/$bdev $vnd $mdl`"
		fi
	else
		echo -e "    $bhost: Unknown $rdev"
	fi
}

function check_host () {
	local found=0
	local pController=
	while read shost ; do
		host=`dirname "$shost"`
		controller=`dirname "$host"`
		bhost=`basename "$host"`
		if [[ "$controller" != "$pController" ]] ; then
			pController="$controller"
			describe_controller "$controller"
		fi
		for dev in $host/target*/*/block/* ; do
			if [[ "${dev: -1}" == '*' ]] ; then
				echo -e "    $bhost: [Empty]"
			else
				describe_device "$dev"
			fi
		done
	done
}

find /sys/devices/ -name scsi_host |check_host