Back to Engineering Notes
100 Days of Cloud (Azure)Engineering Note

Create and Attach Managed Disks

Create and attach a Managed Disk to a Virtual Machine in Microsoft Azure for additional storage.

🎯 Objective

Create and attach a Managed Disk to a Virtual Machine in Microsoft Azure for additional storage.

🧠 What is a Managed Disk?

A Managed Disk is a storage disk managed by Azure for use with Virtual Machines.

It provides:

Persistent storage
High availability
Automatic management by Azure

🏗️ How It Works

plain text
Azure Disk → Attach → Virtual Machine → Mount → Use Storage

📊 Disk Types

🛠️ Method 1: Create & Attach via Azure Portal

1️⃣ Go to Virtual Machine

Navigate to:

Azure Portal → Virtual Machines

2️⃣ Select Your VM

Choose the VM to attach disk

3️⃣ Open Disks Section

Click:

Settings → Disks

4️⃣ Add New Disk

Click:

Create and attach a new disk

5️⃣ Configure Disk

Fill in:

Name → Example: my-data-disk
Size (GiB) → e.g., 30
Type → Standard SSD / Premium SSD

6️⃣ Click Save

👉 Azure will:

Create disk
Attach it to VM

🔍 Verify Disk Attached

Go to VM → Disks
Confirm disk is listed

💻 Mount Disk in VM (Linux)

1️⃣ Connect via SSH

plain text
ssh azureuser@<public-ip>

2️⃣ List Disks

plain text
lsblk

3️⃣ Create Filesystem

plain text
sudo mkfs.ext4 /dev/sdc

4️⃣ Create Mount Point

plain text
sudo mkdir /data

5️⃣ Mount Disk

plain text
sudo mount /dev/sdc /data

6️⃣ Verify

plain text
df -h

⚙️ Method 2: Using Azure CLI

📌 Create Disk

plain text
az disk create \
--resource-group <rg-name> \
--name my-data-disk \
--size-gb30

📌 Attach Disk

plain text
az vm disk attach \
--resource-group <rg-name> \
--vm-name <vm-name> \
--name my-data-disk

⚠️ Important Notes

Disk is not usable until mounted
Device name may vary (/dev/sdc, /dev/sdd)
Charges apply based on disk size/type
Use /etc/fstab for persistent mount

🧪 Example Use Case

👉 Add disk for:

Application data
Logs
Database storage

🧠 DevOps Insight

👉 Managed Disks support:

Scalable storage
Separation of compute and storage
Better performance tuning

⚠️ Common Mistakes

❌ Forgetting to format disk
❌ Not mounting disk
❌ Hardcoding wrong device name
❌ Not persisting mount

🎯 Result

A managed disk is successfully created and attached to the VM, providing additional persistent storage ready for use.