Add ephemera storage to Amazon ECS-optimized AMIs (v1)

docker-add-ephemeral.sh

#!/bin/bash -exu

# find ephemeral devices using the metadata service
# note: this will block loading until the metadata service is ready
find_ephemeral_devices() {
    echo "Querying metadata instance store for ephemeral volumes" >&2
    local DEVICE_NOT_FOUND=0
    for d in $(curl -s "http://169.254.169.254/latest/meta-data/block-device-mapping/" | grep ephemeral); do
       NAME=$(curl -s "http://169.254.169.254/latest/meta-data/block-device-mapping/$d")
       DEVICE_NAME="/dev/$NAME"
       echo "Detected ephemeral device $d corresponding to $DEVICE_NAME" >&2
       # if block device (-b)
       if [[ -b "$DEVICE_NAME" ]]; then
          echo "$DEVICE_NAME"
          DEVICE_NOT_FOUND=0
       else
          echo "Couldn't find device $DEVICE_NAME" >&2
          DEVICE_NOT_FOUND=1
       fi
    done
    return ${DEVICE_NOT_FOUND}
}

# on nvme instances the device names don't match what AWS reports, so just filter by model name
find_nvme_ephemeral() {
  lsblk -o KNAME,MODEL | grep "Amazon EC2 NVMe Instance Storage" | awk '{ print "/dev/"$1 }'
}

METADATA_DEVICES=$(find_ephemeral_devices)
NVME_DEVICES=$(find_nvme_ephemeral)

DEVS=/dev/xvdcz
[[ ! -z "$NVME_DEVICES" ]] && DEVS="$NVME_DEVICES $DEVS"
[[ ! -z "$METADATA_DEVICES" ]] && DEVS="$METADATA_DEVICES $DEVS"

echo "Updating docker storage devices to '$DEVS'"
sed -i -e "s;DEVS=.*;DEVS=\"${DEVS}\";g"  /etc/sysconfig/docker-storage-setup