This script automatically mount ephemeral disks in EC2 nitro instances.

mount_ec2_ephemeral.sh

#!/usr/bin/env bash

# Mandatory: apt install nvme-cli

# Mount point (directory)
TARGET_MOUNT=/data/tmp

# Raid info
TARGET_RAID_DEVICE=/dev/md0
TARGET_RAID_LABEL=RAID0

storages=()

echo "*** Ephemeral mount has been started"

# Find ephemeral storages
for EPHEMERAL_DISK in $(sudo nvme list | grep 'Amazon EC2 NVMe Instance Storage' | awk '{ print $1 }'); do
        storages+=($EPHEMERAL_DISK)
        echo "Found ephemeral disk: $EPHEMERAL_DISK"
done

umount $TARGET_MOUNT

DEVICES="${#storages[@]}"

if [ "$DEVICES" == "" ] || [ "$DEVICES" == "0" ]; then
  echo "This machine doesn't have any EPHEMERAL disk"
elif [ "$DEVICES" == "1" ]; then
  echo "Only one EPHEMERAL DISK are found: create simple xfs (${storages[@]})"
  mkfs.xfs -f -L DISK1 ${storages[@]}
  mount ${storages[0]} $TARGET_MOUNT
else
  echo "More than one EPHEMERAL DISK are found: creating RAID 0 between ${storages[@]}"
  mdadm --stop $TARGET_RAID_DEVICE
  mdadm --create --verbose $TARGET_RAID_DEVICE --level=0 --name=$TARGET_RAID_LABEL --raid-devices=${DEVICES} ${storages[@]}
  mkfs.xfs -f -L $TARGET_RAID_LABEL $TARGET_RAID_DEVICE
  #echo "UUID=$(/usr/sbin/blkid -s UUID -o value $TARGET_RAID_DEVICE) $TARGET_MOUNT  xfs  defaults,nofail  0  2" | sudo tee -a /etc/fstab
  mount LABEL=$TARGET_RAID_LABEL $TARGET_MOUNT
fi



echo "*** Ephemeral mount ended"