# How Do I Add a Second Data Disk to a Node in a CCE Cluster?

You can use the pre-installation script feature to configure CCE cluster nodes (ECSs).

Before using this feature, write a script that can format data disks and save it to your OBS bucket. Then, inject a command line that will automatically execute the disk formatting script when the node is up. The script specifies the size of each docker data disk (for example, the default docker disk is 100 GB and the additional disk is 110 GB) and the mount path (/data/code) of the additional disk. In this example, the script is named formatdisk.sh. Note that the script must be run by the root user.

Example command line:

    cd /tmp;curl -k -X GET OBS bucket address /formatdisk.sh -1 -O;fdisk -l;sleep 30;bash -x formatdisk.sh 100 /data/code;fdisk -l

Example script (formatdisk.sh):

    dockerdisksize=$1
    mountdir=$2
    systemdisksize=40
    i=0
    while [ 20 -gt $i ]; do
        echo $i;
        if [ $(lsblk -o KNAME,TYPE | grep disk | grep -v nvme | awk '{print $1}' | awk '{ print "/dev/"$1}' |wc -l) -ge 3 ]; then
            break
        else
            sleep 5
        fi;
        i=$[i+1]
    done
    all_devices=$(lsblk -o KNAME,TYPE | grep disk | grep -v nvme | awk '{print $1}' | awk '{ print "/dev/"$1}')
    for device in ${all_devices[@]}; do
        isRawDisk=$(lsblk -n $device 2>/dev/null | grep disk | wc -l)
        if [[ ${isRawDisk} > 0 ]]; then
            # is it partitioned ?
            match=$(lsblk -n $device 2>/dev/null | grep -v disk | wc -l)
            if [[ ${match} > 0 ]]; then
                # already partited
                [[ -n "${DOCKER_BLOCK_DEVICES}" ]] && echo "Raw disk ${device} has been partition, will skip this device"
                continue
            fi
        else
            isPart=$(lsblk -n $device 2>/dev/null | grep part | wc -l)
            if [[ ${isPart} -ne 1 ]]; then
                # not parted
                [[ -n "${DOCKER_BLOCK_DEVICES}" ]] && echo "Disk ${device} has not been partition, will skip this device"
                continue
            fi
            # is used ?
            match=$(lsblk -n $device 2>/dev/null | grep -v part | wc -l)
            if [[ ${match} > 0 ]]; then
                # already used
                [[ -n "${DOCKER_BLOCK_DEVICES}" ]] && echo "Disk ${device} has been used, will skip this device"
                continue
            fi
            isMount=$(lsblk -n -o MOUNTPOINT $device 2>/dev/null)
            if [[ -n ${isMount} ]]; then
                # already used
                [[ -n "${DOCKER_BLOCK_DEVICES}" ]] && echo "Disk ${device} has been used, will skip this device"
                continue
            fi
            isLvm=$(sfdisk -lqL 2>>/dev/null | grep $device | grep "8e.*Linux LVM")
            if [[ ! -n ${isLvm} ]]; then
                # part system type is not Linux LVM
                [[ -n "${DOCKER_BLOCK_DEVICES}" ]] && echo "Disk ${device} system type is not Linux LVM, will skip this device"
                continue
            fi
        fi
        block_devices_size=$(lsblk -n -o SIZE $device 2>/dev/null | awk '{ print $1}')
        if [[ ${block_devices_size}"x" != "${dockerdisksize}Gx" ]] && [[ ${block_devices_size}"x" != "${systemdisksize}Gx" ]]; then
    echo "n
    p
    1

    w
    " | fdisk $device
            mkfs -t ext4 ${device}1
            mkdir -p $mountdir
            echo "${device}1  $mountdir ext4  noatime  0 0" | tee -a /etc/fstab >/dev/null
            mount $mountdir
        fi
    done

Parent topic: Reference