Вопросы по файловым системам

Проблема

Есть внешняя система хранения данных. Расширяем физический диск (т.е. добавляем новый винт потом RAID Expand, затем Volume Expand). Все зашибись физический размер увеличился но система естественно этого не видит, как ее заставить увидеть новый размер? Без перезагрузки естественно.

Система CentOS 5.4 

Решение

Можно использовать такой скрипт (мы не ищем легких путей):

#!/bin/bash
# Skript to rescan SCSI bus, using the
# scsi add-single-device mechanism
# (w) 1998-03-19 Kurt Garloff <kurt@garloff.de> (c) GNU GPL
# (w) 2003-07-16 Kurt Garloff <garloff@suse.de> (c) GNU GPL
# $Id: rescan-scsi-bus.sh,v 1.15 2004/05/08 14:47:13 garloff Exp $

setcolor ()
{
  red="\e[0;31m"
  green="\e[0;32m"
  yellow="\e[0;33m"
  norm="\e[0;0m"
}

unsetcolor ()
{
  red=""; green=""
  yellow=""; norm=""
}

# Return hosts. sysfs must be mounted
findhosts_26 ()
{
  hosts=
  if ! ls /sys/class/scsi_host/host* >/dev/null 2>&1; then
    echo "No SCSI host adapters found in sysfs"
    exit 1;
    #hosts=" 0"
    #return
  fi
  for hostdir in /sys/class/scsi_host/host*; do
    hostno=${hostdir#/sys/class/scsi_host/host}
    hostname=`cat $hostdir/proc_name`
    hosts="$hosts $hostno"
    echo "Host adapter $hostno ($hostname) found."
  done
}

# Return hosts. /proc/scsi/HOSTADAPTER/? must exist
findhosts ()
{
  hosts=
  for driverdir in /proc/scsi/*; do
    driver=${driverdir#/proc/scsi/}
    if test $driver = scsi -o $driver = sg -o $driver = dummy -o $driver = device_info; then continue; fi
    for hostdir in $driverdir/*; do
      name=${hostdir#/proc/scsi/*/}
      if test $name = add_map -o $name = map -o $name = mod_parm; then continue; fi
      num=$name
      driverinfo=$driver
      if test -r $hostdir/status; then
        num=$(printf '%d\n' `sed -n 's/SCSI host number://p' $hostdir/status`)
        driverinfo="$driver:$name"
      fi
      hosts="$hosts $num"
      echo "Host adapter $num ($driverinfo) found."
    done
  done
}

# Test if SCSI device $host $channen $id $lun exists
# Outputs description from /proc/scsi/scsi, returns new
testexist ()
{
  grepstr="scsi$host Channel: 0*$channel Id: 0*$id Lun: 0*$lun"
  new=`cat /proc/scsi/scsi | grep -e"$grepstr"`
  if test ! -z "$new"; then
    cat /proc/scsi/scsi | grep -e"$grepstr"
    cat /proc/scsi/scsi | grep -A2 -e"$grepstr" | tail -n2 | pr -o4 -l1
  fi
}

# Perform search (scan $host)
dosearch ()
{
  for channel in $channelsearch; do
    for id in $idsearch; do
      for lun in $lunsearch; do
        new=
        devnr="$host $channel $id $lun"
        echo "Scanning for device $devnr ..."
        printf "${yellow}OLD: $norm"
        testexist
        if test ! -z "$remove" -a ! -z "$new"; then
          # Device exists and we're in remove mode, so remove and readd
          echo "scsi remove-single-device $devnr" >/proc/scsi/scsi
          echo "scsi add-single-device $devnr" >/proc/scsi/scsi
          printf "\r\x1b[A\x1b[A\x1b[A${yellow}OLD: $norm"
          testexist
          if test -z "$new"; then
            printf "\r${red}DEL: $norm\r\n\n\n\n"; let rmvd+=1;
          fi
        fi
        if test -z "$new"; then
          # Device does not exist, try to add
          printf "\r${green}NEW: $norm"
          echo "scsi add-single-device $devnr" >/proc/scsi/scsi
          testexist
          if test -z "$new"; then
            # Device not present
            printf "\r\x1b[A";
            # Optimization: if lun==0, stop here (only if in non-remove mode)
            if test $lun = 0 -a -z "$remove" -a $optscan = 1; then
              break;
            fi
          else
            let found+=1;
          fi
        fi
      done
    done
  done
}

# main
if test @$1 = @--help -o @$1 = @-h -o @$1 = @-?; then
    echo "Usage: rescan-scsi-bus.sh [options] [host [host ...]]"
    echo "Options:"
    echo " -l activates scanning for LUNs 0-7    [default: 0]"
    echo " -w scan for target device IDs 0 .. 15 [default: 0-7]"
    echo " -c enables scanning of channels 0 1   [default: 0]"
    echo " -r enables removing of devices        [default: disabled]"
    echo "--remove:        same as -r"
    echo "--nooptscan:     don't stop looking for LUNs is 0 is not found"
    echo "--color:         use coloured prefixes OLD/NEW/DEL"
    echo "--hosts=LIST:    Scan only host(s) in LIST"
    echo "--channels=LIST: Scan only channel(s) in LIST"
    echo "--ids=LIST:      Scan only target ID(s) in LIST"
    echo "--luns=LIST:     Scan only lun(s) in LIST"
    echo " Host numbers may thus be specified either directly on cmd line (deprecated) or"
    echo " or with the --hosts=LIST parameter (recommended)."
    echo "LIST: A[-B][,C[-D]]... is a comma separated list of single values and ranges"
    echo " (No spaces allowed.)"
    exit 0
fi

expandlist ()
{
    list=$1
    result=""
    first=${list%%,*}
    rest=${list#*,}
    while test ! -z "$first"; do
        beg=${first%%-*};
        if test "$beg" = "$first"; then
            result="$result $beg";
        else
            end=${first#*-}
            result="$result `seq $beg $end`"
        fi
        test "$rest" = "$first" && rest=""
        first=${rest%%,*}
        rest=${rest#*,}
    done
    echo $result
}

if test ! -d /proc/scsi/; then
  echo "Error: SCSI subsystem not active"
  exit 1
fi

# defaults
unsetcolor
lunsearch="0"
idsearch=`seq 0 7`
channelsearch="0"
remove=""
optscan=1
if test -d /sys/class/scsi_host; then
  findhosts_26
else
  findhosts
fi

# Scan options
opt="$1"
while test ! -z "$opt" -a -z "${opt##-*}"; do
  opt=${opt#-}
  case "$opt" in
    l) lunsearch=`seq 0 7`;;
    w) idsearch=`seq 0 15`;;
    c) channelsearch="0 1";;
    r) remove=1;;
    -remove)      remove=1;;
    -hosts=*)     arg=${opt#-hosts=};   hosts=`expandlist $arg`;;
    -channels=*)  arg=${opt#-channels=};channelsearch=`expandlist $arg`;;
    -ids=*)   arg=${opt#-ids=};         idsearch=`expandlist $arg`;;
    -luns=*)  arg=${opt#-luns=};        lunsearch=`expandlist $arg`;;
    -color) setcolor;;
    -nooptscan) optscan=0;;
    *) echo "Unknown option -$opt !";;
  esac
  shift
  opt="$1"
done

# Hosts given ?
if test "@$1" != "@"; then
  hosts=$*;
fi

echo "Scanning hosts $hosts channels $channelsearch for "
echo " SCSI target IDs " $idsearch ", LUNs " $lunsearch
test -z "$remove" || echo " and remove devices that have disappeared"
declare -i found=0
declare -i rmvd=0
for host in $hosts; do
  dosearch;
done
echo "$found new device(s) found.               "
echo "$rmvd device(s) removed.               "

2f13: данный скрипт действительно идет в sg3-utils и нужен для того чтобы добавить или удалить SCSI устройство без перезагрузки, размер уже подключенного устройства при этом не изменяется, т.е. он просто сканирует шину.
Реальнг для рескана размера в режиме онлайн нужно выполнить команду echo 1 > /sys/block/sdX/device/rescan
Найдено тут: http://www.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/html/Online_Storage_Reconfiguration_Guide/online-iscsi-resizing.html

Это работает.

Если что, вот скрипт рескана размера для всех блочных устройств
Код

#!/bin/sh

block_dir=/sys/block

echo "Rescan block device SIZE:"
for dir in `ls $block_dir`; do
    root_path=$block_dir/$dir
    dev_path=$block_dir/$dir/device
    rescan_fpath=$dev_path/rescan

    if [ -e $rescan_fpath ]; then
        rev=`cat $dev_path/rev`
        vendor=`cat $dev_path/vendor`
        model=`cat $dev_path/model`
        old_sectr=`cat $root_path/size`
        echo -n "Rescan size for '$vendor $model rev. $rev': "
        echo 1 >$rescan_fpath
        [ "$?" = "0" ] && echo -n "OK!" || echo -n "FAIL!!!"

        new_sectr=`cat $root_path/size`
        echo " (OLD sectors '$old_sectr', NEW sectors '$new_sectr')"
    fi
done

Проблема

На сервере под управлением Linux собран программный RAID5 на 10 SCSI-дисках. Один диск в этом массиве помечен как faulty.

Как узнать Host, Channel, ID и LUN этого диска?

Решение

[root@nslb4 ~]# cat /proc/mdstat
Personalities : [raid1]
md5 : active raid1 sdb2[1] sda2[0]
      55038592 blocks [2/2] [UU]

md2 : active raid1 sdb3[1] sda3[0]
      5245120 blocks [2/2] [UU]

md3 : active raid1 sdb5[1] sda5[0]
      3148608 blocks [2/2] [UU]

md4 : active raid1 sdb6[1] sda6[0]
      2096384 blocks [2/2] [UU]

md1 : active raid1 sdb7[1] sda7[0]
      2096384 blocks [2/2] [UU]

md0 : active raid1 sdb1[1] sda1[0]
      4192832 blocks [2/2] [UU]

unused devices: <none>
[root@nslb4 ~]# cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
  Vendor: FUJITSU  Model: MAW3073NC        Rev: 0104
  Type:   Direct-Access                    ANSI SCSI revision: 03
Host: scsi0 Channel: 00 Id: 01 Lun: 00
  Vendor: FUJITSU  Model: MAW3073NC        Rev: 0104
  Type:   Direct-Access                    ANSI SCSI revision: 03
Host: scsi0 Channel: 00 Id: 06 Lun: 00
  Vendor: ESG-SHV  Model: SCA HSBP M30     Rev: 1.08
  Type:   Processor                        ANSI SCSI revision: 02