Set up alternate mount point for SCSI/NVMe local SSD by UUID in…

cluster/common.sh

@@ -668,6 +668,7 @@ ENABLE_PROMETHEUS_TO_SD: $(yaml-quote ${ENABLE_PROMETHEUS_TO_SD:-false})
 ENABLE_POD_PRIORITY: $(yaml-quote ${ENABLE_POD_PRIORITY:-})
 CONTAINER_RUNTIME: $(yaml-quote ${CONTAINER_RUNTIME:-})
 CONTAINER_RUNTIME_ENDPOINT: $(yaml-quote ${CONTAINER_RUNTIME_ENDPOINT:-})
+NODE_LOCAL_SSDS_EXT: $(yaml-quote ${NODE_LOCAL_SSDS_EXT:-})
 LOAD_IMAGE_COMMAND: $(yaml-quote ${LOAD_IMAGE_COMMAND:-})
 EOF
   if [ -n "${KUBELET_PORT:-}" ]; then

cluster/gce/config-default.sh

@@ -36,6 +36,11 @@ MASTER_ROOT_DISK_SIZE=${MASTER_ROOT_DISK_SIZE:-$(get-master-root-disk-size)}
 NODE_DISK_TYPE=${NODE_DISK_TYPE:-pd-standard}
 NODE_DISK_SIZE=${NODE_DISK_SIZE:-100GB}
 NODE_LOCAL_SSDS=${NODE_LOCAL_SSDS:-0}
+# An extension to local SSDs allowing users to specify block/fs and SCSI/NVMe devices
+# Format of this variable will be "#,scsi/nvme,block/fs" you can specify multiple
+# configurations by seperating them by a semi-colon ex. "2,scsi,fs;1,nvme,block"
+# is a request for 2 SCSI formatted and mounted SSDs and 1 NVMe block device SSD.
+NODE_LOCAL_SSDS_EXT=${NODE_LOCAL_SSDS_EXT:-""}
 # Accelerators to be attached to each node. Format "type=<accelerator-type>,count=<accelerator-count>"
 # More information on available GPUs here - https://cloud.google.com/compute/docs/gpus/
 NODE_ACCELERATORS=${NODE_ACCELERATORS:-""}

cluster/gce/gci/configure-helper.sh

@@ -25,6 +25,9 @@ set -o errexit
 set -o nounset
 set -o pipefail
 
+readonly UUID_MNT_PREFIX="/mnt/disks/by-uuid/google-local-ssds"
+readonly UUID_BLOCK_PREFIX="/dev/disk/by-uuid/google-local-ssds"
+
 function setup-os-params {
   # Reset core_pattern. On GCI, the default core_pattern pipes the core dumps to
   # /sbin/crash_reporter which is more restrictive in saving crash dumps. So for
@@ -85,11 +88,85 @@ function create-dirs {
   fi
 }
 
-# Formats the given device ($1) if needed and mounts it at given mount point
+# Gets the total number of $(1) and $(2) type disks specified
+# by the user in ${NODE_LOCAL_SSDS_EXT}
+function get-local-disk-num() {
+  local interface="${1}"
+  local format="${2}"
+
+  localdisknum=0
+  if [[ ! -z "${NODE_LOCAL_SSDS_EXT}" ]]; then
+    IFS=";" read -r -a ssdgroups <<< "${NODE_LOCAL_SSDS_EXT}"
+    for ssdgroup in "${ssdgroups[@]}"; do
+      IFS="," read -r -a ssdopts <<< "${ssdgroup}"
+      local opnum="${ssdopts[0]}"
+      local opinterface="${ssdopts[1]}"
+      local opformat="${ssdopts[2]}"
+
+      if [[ "${opformat,,}" == "${format,,}" && "${opinterface,,}" == "${interface,,}" ]]; then
+        localdisknum=$((localdisknum+opnum))
+      fi
+    done
+  fi
+}
+
+# Creates a symlink for a ($1) so that it may be used as block storage
+function safe-block-symlink(){
+  local device="${1}"
+  local symdir="${2}"
+  
+  mkdir -p "${symdir}"
+
+  get-or-generate-uuid "${device}"
+  local myuuid="${retuuid}"
+
+  local sym="${symdir}/local-ssd-${myuuid}"
+  # Do not "mkdir -p ${sym}" as that will cause unintended symlink behavior
+  ln -s "${device}" "${sym}"
+  echo "Created a symlink for SSD $ssd at ${sym}"
+  chmod a+w "${sym}"
+}
+
+# Gets a pregenerated UUID from ${ssdmap} if it exists, otherwise generates a new
+# UUID and places it inside ${ssdmap}
+function get-or-generate-uuid(){
+  local device="${1}"
+
+  local ssdmap="/home/kubernetes/localssdmap.txt"
+  echo "Generating or getting UUID from ${ssdmap}"
+
+  if [[ ! -e "${ssdmap}" ]]; then
+    touch "${ssdmap}"
+    chmod +w "${ssdmap}"
+  fi
+
+  # each line of the ssdmap looks like "${device} persistent-uuid"
+  if [[ ! -z $(grep ${device} ${ssdmap}) ]]; then
+    #create symlink based on saved uuid
+    local myuuid=$(grep ${device} ${ssdmap} | cut -d ' ' -f 2)
+  else
+    # generate new uuid and add it to the map
+    local myuuid=$(uuidgen)
+    if [[ ! ${?} -eq 0 ]]; then
+      echo "Failed to generate valid UUID with uuidgen" >&2
+      exit 2
+    fi
+    echo "${device} ${myuuid}" >> "${ssdmap}"
+  fi
+
+  if [[ -z "${myuuid}" ]]; then
+    echo "Failed to get a uuid for device ${device} when symlinking." >&2
+    exit 2
+  fi
+
+  retuuid="${myuuid}"
+}
+
+#Formats the given device ($1) if needed and mounts it at given mount point
 # ($2).
 function safe-format-and-mount() {
-  device=$1
-  mountpoint=$2
+  local device="${1}"
+  local mountpoint="${2}"
 
   # Format only if the disk is not already formatted.
   if ! tune2fs -l "${device}" ; then
@@ -102,18 +179,135 @@ function safe-format-and-mount() {
   mount -o discard,defaults "${device}" "${mountpoint}"
 }
 
-# Local ssds, if present, are mounted at /mnt/disks/ssdN.
+# Gets a devices UUID and bind mounts the device to mount location in
+# /mnt/disks/by-id/
+function unique-uuid-bind-mount(){
+  local mountpoint="${1}"
+  local actual_device="${2}"
+
+  # Trigger udev refresh so that newly formatted devices are propagated in by-uuid
+  udevadm control --reload-rules
+  udevadm trigger
+  udevadm settle 
+
+  # grep the exact match of actual device, prevents substring matching
+  local myuuid=$(ls -l /dev/disk/by-uuid/ | grep "/${actual_device}$" | tr -s ' ' | cut -d ' ' -f 9)
+  # myuuid should be the uuid of the device as found in /dev/disk/by-uuid/ 
+  if [[ -z "${myuuid}" ]]; then
+    echo "Failed to get a uuid for device ${actual_device} when mounting." >&2
+    exit 2
+  fi
+
+  # bindpoint should be the full path of the to-be-bound device
+  local bindpoint="${UUID_MNT_PREFIX}-${interface}-fs/local-ssd-${myuuid}"
+
+  safe-bind-mount "${mountpoint}" "${bindpoint}"
+}
+
+# Bind mounts device at mountpoint to bindpoint
+function safe-bind-mount(){
+  local mountpoint="${1}"
+  local bindpoint="${2}"
+
+  # Mount device to the mountpoint
+  mkdir -p "${bindpoint}"
+  echo "Binding '${mountpoint}' at '${bindpoint}'"
+  mount --bind "${mountpoint}" "${bindpoint}"
+  chmod a+w "${bindpoint}"
+}
+
+
+# Mounts, bindmounts, or symlinks depending on the interface and format
+# of the incoming device
+function mount-ext(){
+  local ssd="${1}"
+  local devicenum="${2}"
+  local interface="${3}"
+  local format="${4}"
+  
+
+  if [[ -z "${devicenum}" ]]; then
+    echo "Failed to get the local disk number for device ${ssd}" >&2
+    exit 2
+  fi
+
+  # TODO: Handle partitioned disks. Right now this code just ignores partitions
+  if [[ "${format}" == "fs" ]]; then
+    if [[ "${interface}" == "scsi" ]]; then
+      local actual_device=$(readlink -f "${ssd}" | cut -d '/' -f 3)
+      # Error checking
+      if [[ "${actual_device}" != sd* ]]; then
+        echo "'actual_device' is not of the correct format. It must be the kernel name of the device, got ${actual_device} instead" >&2
+        exit 1
+      fi
+      local mountpoint="/mnt/disks/ssd${devicenum}"
+    else
+      # This path is required because the existing Google images do not
+      # expose NVMe devices in /dev/disk/by-id so we are using the /dev/nvme instead
+      local actual_device=$(echo ${ssd} | cut -d '/' -f 3)
+      # Error checking
+      if [[ "${actual_device}" != nvme* ]]; then
+        echo "'actual_device' is not of the correct format. It must be the kernel name of the device, got ${actual_device} instead" >&2
+        exit 1
+      fi
+      local mountpoint="/mnt/disks/ssd-nvme${devicenum}"
+    fi
+
+    safe-format-and-mount "${ssd}" "${mountpoint}"
+    # We only do the bindmount if users are using the new local ssd request method
+    # see https://github.com/kubernetes/kubernetes/pull/53466#discussion_r146431894
+    if [[ ! -z "${NODE_LOCAL_SSDS_EXT}" ]]; then
+      unique-uuid-bind-mount "${mountpoint}" "${actual_device}"
+    fi
+  elif [[ "${format}" == "block" ]]; then
+    local symdir="${UUID_BLOCK_PREFIX}-${interface}-block"
+    safe-block-symlink "${ssd}" "${symdir}"
+  else
+    echo "Disk format must be either fs or block, got ${format}"
+  fi
+}
+
+# Local ssds, if present, are mounted or symlinked to their appropriate
+# locations
 function ensure-local-ssds() {
+  get-local-disk-num "scsi" "block"
+  local scsiblocknum="${localdisknum}"
+  local i=0
   for ssd in /dev/disk/by-id/google-local-ssd-*; do
     if [ -e "${ssd}" ]; then
-      ssdnum=`echo ${ssd} | sed -e 's/\/dev\/disk\/by-id\/google-local-ssd-\([0-9]*\)/\1/'`
-      ssdmount="/mnt/disks/ssd${ssdnum}/"
-      mkdir -p ${ssdmount}
-      safe-format-and-mount "${ssd}" ${ssdmount}
-      echo "Mounted local SSD $ssd at ${ssdmount}"
-      chmod a+w ${ssdmount}
+      local devicenum=`echo ${ssd} | sed -e 's/\/dev\/disk\/by-id\/google-local-ssd-\([0-9]*\)/\1/'`
+      if [[ "${i}" -lt "${scsiblocknum}" ]]; then
+        mount-ext "${ssd}" "${devicenum}" "scsi" "block"
+      else
+        # GKE does not set NODE_LOCAL_SSDS so all non-block devices
+        # are assumed to be filesystem devices
+        mount-ext "${ssd}" "${devicenum}" "scsi" "fs"
+      fi
+      i=$((i+1))
+    else
+      echo "No local SCSI SSD disks found."
+    fi
+  done
+
+  # The following mounts or symlinks NVMe devices
+  get-local-disk-num "nvme" "block"
+  local nvmeblocknum="${localdisknum}"
+  local i=0
+  for ssd in /dev/nvme*; do
+    if [ -e "${ssd}" ]; then
+      # This workaround to find if the NVMe device is a disk is required because
+      # the existing Google images does not expose NVMe devices in /dev/disk/by-id
+      if [[ `udevadm info --query=property --name=${ssd} | grep DEVTYPE | sed "s/DEVTYPE=//"` == "disk" ]]; then
+        local devicenum=`echo ${ssd} | sed -e 's/\/dev\/nvme0n\([0-9]*\)/\1/'`
+        if [[ "${i}" -lt "${nvmeblocknum}" ]]; then
+          mount-ext "${ssd}" "${devicenum}" "nvme" "block"
+        else
+          mount-ext "${ssd}" "${devicenum}" "nvme" "fs"
+        fi
+        i=$((i+1))
+      fi
     else
-      echo "No local SSD disks found."
+      echo "No local NVMe SSD disks found."
     fi
   done
 }

cluster/gce/util.sh

@@ -18,6 +18,8 @@
 
 # Use the config file specified in $KUBE_CONFIG_FILE, or default to
 # config-default.sh.
+readonly GCE_MAX_LOCAL_SSD=8
+
 KUBE_ROOT=$(dirname "${BASH_SOURCE}")/../..
 source "${KUBE_ROOT}/cluster/gce/${KUBE_CONFIG_FILE-"config-default.sh"}"
 source "${KUBE_ROOT}/cluster/common.sh"
@@ -37,6 +39,11 @@ else
   exit 1
 fi
 
+if [[ ${NODE_LOCAL_SSDS} -ge 1 ]] && [[ ! -z ${NODE_LOCAL_SSDS_EXT} ]] ; then
+  echo -e "${color_red}Local SSD: Only one of NODE_LOCAL_SSDS and NODE_LOCAL_SSDS_EXT can be specified at once${color_norm}" >&2
+  exit 2
+fi
+
 if [[ "${MASTER_OS_DISTRIBUTION}" == "gci" ]]; then
     DEFAULT_GCI_PROJECT=google-containers
     if [[ "${GCI_VERSION}" == "cos"* ]]; then
@@ -546,6 +553,29 @@ function get-template-name-from-version() {
   echo "${NODE_INSTANCE_PREFIX}-template-${1}" | cut -c 1-63 | sed 's/[\.\+]/-/g;s/-*$//g'
 }
 
+# validates the NODE_LOCAL_SSDS_EXT variable 
+function validate-node-local-ssds-ext(){
+  ssdopts="${1}"
+
+  if [[ -z "${ssdopts[0]}" || -z "${ssdopts[1]}" || -z "${ssdopts[2]}" ]]; then
+	  echo -e "${color_red}Local SSD: NODE_LOCAL_SSDS_EXT is malformed, found ${ssdopts[0]-_},${ssdopts[1]-_},${ssdopts[2]-_} ${color_norm}" >&2
+    exit 2
+  fi
+  if [[ "${ssdopts[1]}" != "scsi" && "${ssdopts[1]}" != "nvme" ]]; then
+    echo -e "${color_red}Local SSD: Interface must be scsi or nvme, found: ${ssdopts[1]} ${color_norm}" >&2
+    exit 2
+  fi
+  if [[ "${ssdopts[2]}" != "fs" && "${ssdopts[2]}" != "block" ]]; then
+    echo -e "${color_red}Local SSD: Filesystem type must be fs or block, found: ${ssdopts[2]} ${color_norm}"  >&2
+    exit 2
+  fi
+  local_ssd_ext_count=$((local_ssd_ext_count+ssdopts[0]))
+  if [[ "${local_ssd_ext_count}" -gt "${GCE_MAX_LOCAL_SSD}" || "${local_ssd_ext_count}" -lt 1 ]]; then
+    echo -e "${color_red}Local SSD: Total number of local ssds must range from 1 to 8, found: ${local_ssd_ext_count} ${color_norm}" >&2
+    exit 2
+  fi
+}
+
 # Robustly try to create an instance template.
 # $1: The name of the instance template.
 # $2: The scopes flag.
@@ -587,6 +617,19 @@ function create-node-template() {
   fi
 
   local local_ssds=""
+  local_ssd_ext_count=0
+  if [[ ! -z ${NODE_LOCAL_SSDS_EXT-""} ]]; then
+    IFS=";" read -r -a ssdgroups <<< ${NODE_LOCAL_SSDS_EXT}
+    for ssdgroup in "${ssdgroups[@]}"
+    do
+      IFS="," read -r -a ssdopts <<< ${ssdgroup}
+      validate-node-local-ssds-ext ${ssdopts}
+      for i in $(seq ${ssdopts[0]}); do
+        local_ssds="$local_ssds--local-ssd=interface=${ssdopts[1]} "
+      done
+    done
+  fi
+  
   if [[ ! -z ${NODE_LOCAL_SSDS+x} ]]; then
     # The NODE_LOCAL_SSDS check below fixes issue #49171
     # Some versions of seq will count down from 1 if "seq 0" is specified
@@ -596,6 +639,7 @@ function create-node-template() {
       done
     fi
   fi
+  
 
   local network=$(make-gcloud-network-argument \
     "${NETWORK_PROJECT}" \