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@trentmswanson
Last active December 3, 2022 08:22
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Linux bash script to partition and format all data disks in azure
#!/bin/bash
# An set of disks to ignore from partitioning and formatting
BLACKLIST="/dev/sda|/dev/sdb"
# Base directory to hold the data* files
DATA_BASE="/media"
usage() {
echo "Usage: $(basename $0) <new disk>"
}
scan_for_new_disks() {
# Looks for unpartitioned disks
declare -a RET
DEVS=($(ls -1 /dev/sd*|egrep -v "${BLACKLIST}"|egrep -v "[0-9]$"))
for DEV in "${DEVS[@]}";
do
# Check each device if there is a "1" partition. If not,
# "assume" it is not partitioned.
if [ ! -b ${DEV}1 ];
then
RET+="${DEV} "
fi
done
echo "${RET}"
}
get_next_mountpoint() {
DIRS=($(ls -1d ${DATA_BASE}/data* 2>&1| sort --version-sort))
if [ -z "${DIRS[0]}" ];
then
echo "${DATA_BASE}/data1"
return
else
IDX=$(echo "${DIRS[${#DIRS[@]}-1]}"|tr -d "[a-zA-Z/]" )
IDX=$(( ${IDX} + 1 ))
echo "${DATA_BASE}/data${IDX}"
fi
}
add_to_fstab() {
UUID=${1}
MOUNTPOINT=${2}
grep "${UUID}" /etc/fstab >/dev/null 2>&1
if [ ${?} -eq 0 ];
then
echo "Not adding ${UUID} to fstab again (it's already there!)"
else
LINE="UUID=\"${UUID}\"\t${MOUNTPOINT}\text4\tnoatime,nodiratime,nodev,noexec,nosuid\t1 2"
echo -e "${LINE}" >> /etc/fstab
fi
}
is_partitioned() {
# Checks if there is a valid partition table on the
# specified disk
OUTPUT=$(sfdisk -l ${1} 2>&1)
grep "No partitions found" "${OUTPUT}" >/dev/null 2>&1
return "${?}"
}
has_filesystem() {
DEVICE=${1}
OUTPUT=$(file -L -s ${DEVICE})
grep filesystem <<< "${OUTPUT}" > /dev/null 2>&1
return ${?}
}
do_partition() {
# This function creates one (1) primary partition on the
# disk, using all available space
DISK=${1}
echo "n
p
1
w"| fdisk "${DISK}" > /dev/null 2>&1
#
# Use the bash-specific $PIPESTATUS to ensure we get the correct exit code
# from fdisk and not from echo
if [ ${PIPESTATUS[1]} -ne 0 ];
then
echo "An error occurred partitioning ${DISK}" >&2
echo "I cannot continue" >&2
exit 2
fi
}
if [ -z "${1}" ];
then
DISKS=($(scan_for_new_disks))
else
DISKS=("${@}")
fi
echo "Disks are ${DISKS[@]}"
for DISK in "${DISKS[@]}";
do
echo "Working on ${DISK}"
is_partitioned ${DISK}
if [ ${?} -ne 0 ];
then
echo "${DISK} is not partitioned, partitioning"
do_partition ${DISK}
fi
PARTITION=$(fdisk -l ${DISK}|grep -A 1 Device|tail -n 1|awk '{print $1}')
has_filesystem ${PARTITION}
if [ ${?} -ne 0 ];
then
echo "Creating filesystem on ${PARTITION}."
#echo "Press Ctrl-C if you don't want to destroy all data on ${PARTITION}"
#sleep 5
mkfs -j -t ext4 ${PARTITION}
fi
MOUNTPOINT=$(get_next_mountpoint)
echo "Next mount point appears to be ${MOUNTPOINT}"
[ -d "${MOUNTPOINT}" ] || mkdir "${MOUNTPOINT}"
read UUID FS_TYPE < <(blkid -u filesystem ${PARTITION}|awk -F "[= ]" '{print $3" "$5}'|tr -d "\"")
add_to_fstab "${UUID}" "${MOUNTPOINT}"
echo "Mounting disk ${PARTITION} on ${MOUNTPOINT}"
mount "${MOUNTPOINT}"
done
@neal-shah
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neal-shah commented May 18, 2020

So I was getting errors when I hit the do_partition() function, fdisk wasn't recognising the inputs.

I changed this to:

DISK=${1}
    (
        echo n
        echo p
        echo 1
        echo
        echo
        echo w
    ) | fdisk "${DISK}" > /dev/null 2>&1

And it seemed to work - tested on Ubuntu 18.04.4 LTS (GNU/Linux 5.3.0-1020-azure x86_64)

By the way, great script - saved me a lot of time!!

@philthynz
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On CentOS I am getting an error:

Disks are
syntax error near unexpected token `('
`    read UUID FS_TYPE < <(blkid -u filesystem ${PARTITION}|awk -F "[= ]" '{print $3" "$5}'|tr -d "\"")'

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