LVM Extend Shell Script Linux

Safely extend LVM disk space on Linux with a script that runs pvresize, lvextend, and filesystem grow in the correct order.

What this script does

Rescan SCSI/SATA disks for new space
Extends physical volume (PV) and logical volume (LV)
Grows XFS or ext4 filesystem online
Pre-flight checks before making changes
Logs every step for audit trail

Prerequisites

LVM setup on server
Unallocated space on disk or new disk added
Root access
Backup before resizing

Step 1: Save the script

sudo nano /usr/local/bin/lvm-extend.sh
sudo chmod +x /usr/local/bin/lvm-extend.sh

Step 2: Full script (scroll to read)

lvm-extend.sh

#!/usr/bin/env bash
set -euo pipefail

LV_PATH="/dev/mapper/vg0-root"
PV="/dev/sda3"
FS_TYPE="xfs"
MOUNT="/"
LOG="/var/log/lvm-extend.log"

log(){ echo "[$(date '+%F %T')] $*" | tee -a "$LOG"; }
die(){ log "ERROR: $*"; exit 1; }

[[ $EUID -eq 0 ]] || die "Run as root"
log "Starting LVM extend for $LV_PATH"

log "Rescanning block devices"
echo 1 > /sys/class/block/$(basename "$(dirname "$PV")")/device/rescan 2>/dev/null || true
partprobe 2>/dev/null || true

log "Extending physical volume: $PV"
pvresize "$PV"

log "Extending logical volume: $LV_PATH (100% FREE)"
lvextend -l +100%FREE "$LV_PATH"

log "Growing filesystem ($FS_TYPE) on $MOUNT"
if [[ "$FS_TYPE" == "xfs" ]]; then
  xfs_growfs "$MOUNT"
else
  resize2fs "$LV_PATH"
fi

log "Done. New size:"
df -h "$MOUNT" | tee -a "$LOG"
lvs "$LV_PATH" | tee -a "$LOG"

Scroll inside the box to read the full script.

Step 3: Configure settings

LV_PATH — e.g. /dev/mapper/vg0-root
FS_TYPE — xfs or ext4
PV — physical volume device

LVM disk extend shell script on Linux server

Step 4: Test manually

sudo lvs && sudo df -h

sudo /usr/local/bin/lvm-extend.sh

Extend LVM Disk on Linux with a Shell Script (lvresize & xfs/ext4)

What this script does

Prerequisites

Step 1: Save the script

Step 2: Full script (scroll to read)

Step 3: Configure settings

Step 4: Test manually

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