cmd/vdev_id/vdev_id

   1 #!/bin/sh
   2 #
   3 # vdev_id: udev helper to generate user-friendly names for JBOD disks
   4 #
   5 # This script parses the file /etc/zfs/vdev_id.conf to map a
   6 # physical path in a storage topology to a channel name.  The
   7 # channel name is combined with a disk enclosure slot number to
   8 # create an alias that reflects the physical location of the drive.
   9 # This is particularly helpful when it comes to tasks like replacing
  10 # failed drives.  Slot numbers may also be re-mapped in case the
  11 # default numbering is unsatisfactory.  The drive aliases will be
  12 # created as symbolic links in /dev/disk/by-vdev.
  13 #
  14 # The currently supported topologies are sas_direct and sas_switch.
  15 # A multipath mode is supported in which dm-mpath devices are
  16 # handled by examining the first-listed running component disk.  In
  17 # multipath mode the configuration file should contain a channel
  18 # definition with the same name for each path to a given enclosure.
  19 #
  20 # The alias keyword provides a simple way to map already-existing
  21 # device symlinks to more convenient names.  It is suitable for
  22 # small, static configurations or for sites that have some automated
  23 # way to generate the mapping file.
  24 #
  25 #
  26 # Some example configuration files are given below.
  27
  28 # #
  29 # # Example vdev_id.conf - sas_direct.
  30 # #
  31 #
  32 # multipath     no
  33 # topology      sas_direct
  34 # phys_per_port 4
  35 # slot          bay
  36 #
  37 # #       PCI_ID  HBA PORT  CHANNEL NAME
  38 # channel 85:00.0 1         A
  39 # channel 85:00.0 0         B
  40 # channel 86:00.0 1         C
  41 # channel 86:00.0 0         D
  42 #
  43 # # Custom mapping for Channel A
  44 #
  45 # #    Linux      Mapped
  46 # #    Slot       Slot      Channel
  47 # slot 1          7         A
  48 # slot 2          10        A
  49 # slot 3          3         A
  50 # slot 4          6         A
  51 #
  52 # # Default mapping for B, C, and D
  53 # slot 1          4
  54 # slot 2          2
  55 # slot 3          1
  56 # slot 4          3
  57
  58 # #
  59 # # Example vdev_id.conf - sas_switch
  60 # #
  61 #
  62 # topology      sas_switch
  63 #
  64 # #       SWITCH PORT  CHANNEL NAME
  65 # channel 1            A
  66 # channel 2            B
  67 # channel 3            C
  68 # channel 4            D
  69
  70 # #
  71 # # Example vdev_id.conf - multipath
  72 # #
  73 #
  74 # multipath yes
  75 #
  76 # #       PCI_ID  HBA PORT  CHANNEL NAME
  77 # channel 85:00.0 1         A
  78 # channel 85:00.0 0         B
  79 # channel 86:00.0 1         A
  80 # channel 86:00.0 0         B
  81
  82 # #
  83 # # Example vdev_id.conf - alias
  84 # #
  85 #
  86 # #     by-vdev
  87 # #     name     fully qualified or base name of device link
  88 # alias d1       /dev/disk/by-id/wwn-0x5000c5002de3b9ca
  89 # alias d2       wwn-0x5000c5002def789e
  90
  91 PATH=/bin:/sbin:/usr/bin:/usr/sbin
  92 CONFIG=/etc/zfs/vdev_id.conf
  93 PHYS_PER_PORT=
  94 DEV=
  95 MULTIPATH=
  96 TOPOLOGY=
  97 BAY=
  98
  99 usage() {
 100         cat << EOF
 101 Usage: vdev_id [-h]
 102        vdev_id <-d device> [-c config_file] [-p phys_per_port]
 103                [-g sas_direct|sas_switch] [-m]
 104
 105   -c    specify name of alernate config file [default=$CONFIG]
 106   -d    specify basename of device (i.e. sda)
 107   -g    Storage network topology [default="$TOPOLOGY"]
 108   -m    Run in multipath mode
 109   -p    number of phy's per switch port [default=$PHYS_PER_PORT]
 110   -h    show this summary
 111 EOF
 112         exit 0
 113 }
 114
 115 map_slot() {
 116         local LINUX_SLOT=$1
 117         local CHANNEL=$2
 118         local MAPPED_SLOT=
 119
 120         MAPPED_SLOT=`awk "\\$1 == \"slot\" && \\$2 == ${LINUX_SLOT} && \
 121                         \\$4 ~ /^${CHANNEL}$|^$/ { print \\$3; exit }" $CONFIG`
 122         if [ -z "$MAPPED_SLOT" ] ; then
 123                 MAPPED_SLOT=$LINUX_SLOT
 124         fi
 125         printf "%d" ${MAPPED_SLOT}
 126 }
 127
 128 map_channel() {
 129         local MAPPED_CHAN=
 130         local PCI_ID=$1
 131         local PORT=$2
 132
 133         case $TOPOLOGY in
 134                 "sas_switch")
 135                 MAPPED_CHAN=`awk "\\$1 == \"channel\" && \\$2 == ${PORT} \
 136                         { print \\$3; exit }" $CONFIG`
 137                 ;;
 138                 "sas_direct")
 139                 MAPPED_CHAN=`awk "\\$1 == \"channel\" && \
 140                         \\$2 == \"${PCI_ID}\" && \\$3 == ${PORT} \
 141                         { print \\$4; exit }" $CONFIG`
 142                 ;;
 143         esac
 144         printf "%s" ${MAPPED_CHAN}
 145 }
 146
 147 sas_handler() {
 148         if [ -z "$PHYS_PER_PORT" ] ; then
 149                 PHYS_PER_PORT=`awk "\\$1 == \"phys_per_port\" \
 150                         {print \\$2; exit}" $CONFIG`
 151         fi
 152         PHYS_PER_PORT=${PHYS_PER_PORT:-4}
 153         if ! echo $PHYS_PER_PORT | grep -q -E '^[0-9]+$' ; then
 154                 echo "Error: phys_per_port value $PHYS_PER_PORT is non-numeric"
 155                 exit 1
 156         fi
 157
 158         if [ -z "$MULTIPATH_MODE" ] ; then
 159                 MULTIPATH_MODE=`awk "\\$1 == \"multipath\" \
 160                         {print \\$2; exit}" $CONFIG`
 161         fi
 162
 163         # Use first running component device if we're handling a dm-mpath device
 164         if [ "$MULTIPATH_MODE" = "yes" ] ; then
 165                 # If udev didn't tell us the UUID via DM_NAME, check /dev/mapper
 166                 if [ -z "$DM_NAME" ] ; then
 167                         DM_NAME=`ls -l --full-time /dev/mapper |
 168                                 awk "/\/$DEV$/{print \\$9}"`
 169                 fi
 170
 171                 # For raw disks udev exports DEVTYPE=partition when
 172                 # handling partitions, and the rules can be written to
 173                 # take advantage of this to append a -part suffix.  For
 174                 # dm devices we get DEVTYPE=disk even for partitions so
 175                 # we have to append the -part suffix directly in the
 176                 # helper.
 177                 if [ "$DEVTYPE" != "partition" ] ; then
 178                         PART=`echo $DM_NAME | awk -Fp '/p/{print "-part"$2}'`
 179                 fi
 180
 181                 # Strip off partition information.
 182                 DM_NAME=`echo $DM_NAME | sed 's/p[0-9][0-9]*$//'`
 183                 if [ -z "$DM_NAME" ] ; then
 184                         return
 185                 fi
 186
 187                 # Get the raw scsi device name from multipath -l.  Strip off
 188                 # leading pipe symbols to make field numbering consistent.
 189                 DEV=`multipath -l $DM_NAME |
 190                         awk '/running/{gsub("^[|]"," "); print $3 ; exit}'`
 191                 if [ -z "$DEV" ] ; then
 192                         return
 193                 fi
 194         fi
 195
 196         if echo $DEV | grep -q ^/devices/ ; then
 197                 sys_path=$DEV
 198         else
 199                 sys_path=`udevadm info -q path -p /sys/block/$DEV 2>/dev/null`
 200         fi
 201
 202         # Use positional parameters as an ad-hoc array
 203         set -- $(echo "$sys_path" | tr / ' ')
 204         num_dirs=$#
 205         scsi_host_dir="/sys"
 206
 207         # Get path up to /sys/.../hostX
 208         i=1
 209         while [ $i -le $num_dirs ] ; do
 210                 d=$(eval echo \${$i})
 211                 scsi_host_dir="$scsi_host_dir/$d"
 212                 echo $d | grep -q -E '^host[0-9]+$' && break
 213                 i=$(($i + 1))
 214         done
 215
 216         if [ $i = $num_dirs ] ; then
 217                 return
 218         fi
 219
 220         PCI_ID=$(eval echo \${$(($i -1))} | awk -F: '{print $2":"$3}')
 221
 222         # In sas_switch mode, the directory four levels beneath
 223         # /sys/.../hostX contains symlinks to phy devices that reveal
 224         # the switch port number.  In sas_direct mode, the phy links one
 225         # directory down reveal the HBA port.
 226         port_dir=$scsi_host_dir
 227         case $TOPOLOGY in
 228                 "sas_switch") j=$(($i + 4)) ;;
 229                 "sas_direct") j=$(($i + 1)) ;;
 230         esac
 231
 232         i=$(($i + 1))
 233         while [ $i -le $j ] ; do
 234                 port_dir="$port_dir/$(eval echo \${$i})"
 235                 i=$(($i + 1))
 236         done
 237
 238         PHY=`ls -d $port_dir/phy* 2>/dev/null | head -1 | awk -F: '{print $NF}'`
 239         if [ -z "$PHY" ] ; then
 240                 return
 241         fi
 242         PORT=$(( $PHY / $PHYS_PER_PORT ))
 243
 244         # Look in /sys/.../sas_device/end_device-X for the bay_identifier
 245         # attribute.
 246         end_device_dir=$port_dir
 247         while [ $i -lt $num_dirs ] ; do
 248                 d=$(eval echo \${$i})
 249                 end_device_dir="$end_device_dir/$d"
 250                 if echo $d | grep -q '^end_device' ; then
 251                         end_device_dir="$end_device_dir/sas_device/$d"
 252                         break
 253                 fi
 254                 i=$(($i + 1))
 255         done
 256
 257         SLOT=
 258         case $BAY in
 259         "bay")
 260                 SLOT=`cat $end_device_dir/bay_identifier 2>/dev/null`
 261                 ;;
 262         "phy")
 263                 SLOT=`cat $end_device_dir/phy_identifier 2>/dev/null`
 264                 ;;
 265         "id")
 266                 i=$(($i + 1))
 267                 d=$(eval echo \${$i})
 268                 SLOT=`echo $d | sed -e 's/^.*://'`
 269                 ;;
 270         "lun")
 271                 i=$(($i + 2))
 272                 d=$(eval echo \${$i})
 273                 SLOT=`echo $d | sed -e 's/^.*://'`
 274                 ;;
 275         esac
 276         if [ -z "$SLOT" ] ; then
 277                 return
 278         fi
 279
 280         CHAN=`map_channel $PCI_ID $PORT`
 281         SLOT=`map_slot $SLOT $CHAN`
 282         if [ -z "$CHAN" ] ; then
 283                 return
 284         fi
 285         echo ${CHAN}${SLOT}${PART}
 286 }
 287
 288 alias_handler () {
 289         # Special handling is needed to correctly append a -part suffix
 290         # to partitions of device mapper devices.  The DEVTYPE attribute
 291         # is normally set to "disk" instead of "partition" in this case,
 292         # so the udev rules won't handle that for us as they do for
 293         # "plain" block devices.
 294         #
 295         # For example, we may have the following links for a device and its
 296         # partitions,
 297         #
 298         #  /dev/disk/by-id/dm-name-isw_dibgbfcije_ARRAY0   -> ../../dm-0
 299         #  /dev/disk/by-id/dm-name-isw_dibgbfcije_ARRAY0p1 -> ../../dm-1
 300         #  /dev/disk/by-id/dm-name-isw_dibgbfcije_ARRAY0p2 -> ../../dm-3
 301         #
 302         # and the following alias in vdev_id.conf.
 303         #
 304         #   alias A0 dm-name-isw_dibgbfcije_ARRAY0
 305         #
 306         # The desired outcome is for the following links to be created
 307         # without having explicitly defined aliases for the partitions.
 308         #
 309         #  /dev/disk/by-vdev/A0       -> ../../dm-0
 310         #  /dev/disk/by-vdev/A0-part1 -> ../../dm-1
 311         #  /dev/disk/by-vdev/A0-part2 -> ../../dm-3
 312         #
 313         # Warning: The following grep pattern will misidentify whole-disk
 314         #          devices whose names end with 'p' followed by a string of
 315         #          digits as partitions, causing alias creation to fail. This
 316         #          ambiguity seems unavoidable, so devices using this facility
 317         #          must not use such names.
 318         local DM_PART=
 319         if echo $DM_NAME | grep -q -E 'p[0-9][0-9]*$' ; then
 320                 if [ "$DEVTYPE" != "partition" ] ; then
 321                         DM_PART=`echo $DM_NAME | awk -Fp '/p/{print "-part"$2}'`
 322                 fi
 323         fi
 324
 325         # DEVLINKS attribute must have been populated by already-run udev rules.
 326         for link in $DEVLINKS ; do
 327                 # Remove partition information to match key of top-level device.
 328                 if [ -n "$DM_PART" ] ; then
 329                         link=`echo $link | sed 's/p[0-9][0-9]*$//'`
 330                 fi
 331                 # Check both the fully qualified and the base name of link.
 332                 for l in $link `basename $link` ; do
 333                         alias=`awk "\\$1 == \"alias\" && \\$3 == \"${l}\" \
 334                                         { print \\$2; exit }" $CONFIG`
 335                         if [ -n "$alias" ] ; then
 336                                 echo ${alias}${DM_PART}
 337                                 return
 338                         fi
 339                 done
 340         done
 341 }
 342
 343 while getopts 'c:d:g:mp:h' OPTION; do
 344         case ${OPTION} in
 345         c)
 346                 CONFIG=${OPTARG}
 347                 ;;
 348         d)
 349                 DEV=${OPTARG}
 350                 ;;
 351         g)
 352                 TOPOLOGY=$OPTARG
 353                 ;;
 354         p)
 355                 PHYS_PER_PORT=${OPTARG}
 356                 ;;
 357         m)
 358                 MULTIPATH_MODE=yes
 359                 ;;
 360         h)
 361                 usage
 362                 ;;
 363         esac
 364 done
 365
 366 if [ ! -r $CONFIG ] ; then
 367         exit 0
 368 fi
 369
 370 if [ -z "$DEV" ] ; then
 371         echo "Error: missing required option -d"
 372         exit 1
 373 fi
 374
 375 if [ -z "$TOPOLOGY" ] ; then
 376         TOPOLOGY=`awk "\\$1 == \"topology\" {print \\$2; exit}" $CONFIG`
 377 fi
 378
 379 if [ -z "$BAY" ] ; then
 380         BAY=`awk "\\$1 == \"slot\" {print \\$2; exit}" $CONFIG`
 381 fi
 382
 383 # First check if an alias was defined for this device.
 384 ID_VDEV=`alias_handler`
 385
 386 if [ -z "$ID_VDEV" ] ; then
 387         BAY=${BAY:-bay}
 388         TOPOLOGY=${TOPOLOGY:-sas_direct}
 389         case $TOPOLOGY in
 390                 sas_direct|sas_switch)
 391                         ID_VDEV=`sas_handler`
 392                         ;;
 393                 *)
 394                         echo "Error: unknown topology $TOPOLOGY"
 395                         exit 1
 396                         ;;
 397         esac
 398 fi
 399
 400 if [ -n "$ID_VDEV" ] ; then
 401         echo "ID_VDEV=${ID_VDEV}"
 402         echo "ID_VDEV_PATH=disk/by-vdev/${ID_VDEV}"
 403 fi