Linux Server Inventory Shell Script

CMDBs start with a honest linux server inventory script — a Bash report you can cron weekly and diff when wondering what changed after a migration. This collects CPU, RAM, disk, and network basics in one JSON file.

What this script does

Gathers hostname, kernel, uptime, OS pretty name
Records CPU model and vCPU count, memory used/total
Lists filesystem use for local mounts
Captures ip -br a addresses
Writes timestamped JSON under /var/log

Prerequisites

Standard procps/iproute2 utilities
python3 for JSON escaping (optional jq instead)
Write access to REPORT_DIR

Step 1: Save the script

sudo nano /usr/local/bin/server-inventory.sh
sudo chmod +x /usr/local/bin/server-inventory.sh

Step 2: Full script (scroll to read)

server-inventory.sh

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

REPORT_DIR="/var/log/inventory"
mkdir -p "$REPORT_DIR"
OUT="$REPORT_DIR/latest.json"

host=$(hostname -f 2>/dev/null || hostname)
kernel=$(uname -r)
uptime_s=$(awk '{print int($1)}' /proc/uptime)
os=$(grep PRETTY_NAME /etc/os-release 2>/dev/null | cut -d= -f2 | tr -d '"' || echo unknown)
cpus=$(nproc)
mem=$(free -m | awk '/Mem:/ {printf "%s/%s MB", $3,$2}')
disk=$(df -hP -x tmpfs -x devtmpfs --output=target,pcent | tail -n +2 | tr '\n' '; ')
ips=$(ip -br a | tr '\n' '; ')

export HOST="$host" KERNEL="$kernel" UPTIME="$uptime_s" OS="$os" CPUS="$cpus" MEM="$mem" DISK="$disk" IPS="$ips"

python3 - <<'PY' >"$OUT"
import json, os
from datetime import datetime, timezone
print(json.dumps({
  "timestamp": datetime.now(timezone.utc).isoformat(),
  "hostname": os.environ["HOST"],
  "kernel": os.environ["KERNEL"],
  "uptime_seconds": int(os.environ["UPTIME"]),
  "os": os.environ["OS"],
  "cpu_count": int(os.environ["CPUS"]),
  "memory": os.environ["MEM"],
  "disk_usage": os.environ["DISK"],
  "interfaces": os.environ["IPS"],
}, indent=2))
PY

echo "Wrote $OUT"

Scroll inside the box to read the full script.

Step 3: Configure settings

Extend with dpkg -l or rpm -qa for package lists (slower)
Feed reports into health check script patterns
Avoid storing secrets in inventory output

Linux server inventory shell script JSON report

Step 4: Test manually

./server-inventory.sh

cat /var/log/inventory/latest.json | head

Schedule with cron

sudo crontab -e

Add:

0 6 * * 1 /usr/local/bin/server-inventory.sh >> /var/log/server-inventory.log 2>&1

Linux Server Inventory Shell Script (CPU, RAM, Disk, JSON Report)