How to create and attach an EBS volume to an EC2 instance?

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Attaching an EBS volume to an EC2 instance is a two-part process. The AWS side (creating and attaching the volume) makes the block device available to the instance, but the OS side (formatting and mounting) is what makes it usable. Both parts are required before you can read or write data to the volume. Step 1 — Create the EBS volume in the SAME Availability Zone as the target EC2 instance Step 2 — Attach the volume to the EC2 instance using the Console or CLI (assigns a device name like /dev/sdf) Step 3 — SSH into the EC2 instance Step 4 — Use lsblk or fdisk -l to verify the new device is visible Step 5 — Format the volume with a file system (mkfs.ext4 or mkfs.xfs) Step 6 — Create a mount point directory (mkdir /data) Step 7 — Mount the volume (mount /dev/xvdf /data) Step 8 — (Optional but recommended) Add to /etc/fstab for automatic remounting on reboot # ── AWS SIDE ──────────────────────────────────────────────

# Step 1: Create the volume (MUST be in same AZ as your instance)
aws ec2 create-volume \
  --volume-type gp3 \
  --size 100 \
  --availability-zone us-east-1a \
  --encrypted \
  --tag-specifications 'ResourceType=volume,Tags=[{Key=Name,Value=DataVolume}]'

# Output will include VolumeId: vol-0abc1234567890def

# Step 2: Attach the volume to the EC2 instance
aws ec2 attach-volume \
  --volume-id vol-0abc1234567890def \
  --instance-id i-0123456789abcdef0 \
  --device /dev/sdf

# Wait for attachment to complete
aws ec2 wait volume-in-use --volume-ids vol-0abc1234567890def
echo 'Volume attached successfully!' # ── OS SIDE (run inside the EC2 instance via SSH) ─────────

# Step 3: List block devices to confirm the new volume is visible
lsblk
# You should see: xvdf  202:80  0  100G  0 disk

# Step 4: Check if the volume already has a file system
sudo file -s /dev/xvdf
# Output '/dev/xvdf: data' means it is empty — safe to format

# Step 5: Format the volume with ext4 file system
sudo mkfs.ext4 /dev/xvdf

# Step 6: Create a mount point
sudo mkdir /data

# Step 7: Mount the volume
sudo mount /dev/xvdf /data

# Verify it is mounted
df -h
# Should show: /dev/xvdf   99G   60M   94G   1% /data

# Step 8: Persist mount across reboots by adding to /etc/fstab
# Get the UUID of the device first
sudo blkid /dev/xvdf
# Example output: /dev/xvdf: UUID="abc-123" TYPE="ext4"

# Add to /etc/fstab
echo 'UUID=abc-123  /data  ext4  defaults,nofail  0  2' | sudo tee -a /etc/fstab

# Test the fstab entry
sudo umount /data
sudo mount -a
df -h The device name you specify (/dev/sdf) may appear as /dev/xvdf or /dev/nvme1n1 inside the OS depending on the instance type NVMe-based instances (Nitro) show volumes as /dev/nvme1n1, /dev/nvme2n1, etc. Always use UUID in /etc/fstab instead of device names like /dev/xvdf — device names can change on reboot The nofail option in /etc/fstab prevents boot failures if the EBS volume is not attached You can attach up to 27 EBS volumes to a single EC2 instance (Nitro-based instances support more) After increasing a volume's size (Elastic Volumes), you must resize the file system: sudo resize2fs /dev/xvdf for ext4 or sudo xfs_growfs /data for XFS

How to create and attach an EBS volume to an EC2 instance?

Creating and attaching an EBS volume involves three stages: creating the volume in the same Availability Zone as your EC2 instance, attaching it via the Console or CLI, and then mounting and formatting it inside the OS of the running instance.

How to create and attach an EBS volume to an EC2 instance?

Creating and attaching an EBS volume involves three stages: creating the volume in the same Availability Zone as your EC2 instance, attaching it via the Console or CLI, and then mounting and formatting it inside the OS of the running instance.

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