EBS volumes: gp3 vs io2, snapshots and resizing without downtime

Start as usual. In step 1 you also save two small helper scripts for the Session Manager endpoints from Lesson 13, so later lessons can switch them on and off with one line.

cd C:\aws-lab
aws login --profile saat-admin
$env:AWS_PROFILE = 'saat-admin'
$env:Path += ';C:\Program Files\Amazon\SessionManagerPlugin\bin'
$v = Get-Content C:\aws-lab\saat-vpc.json | ConvertFrom-Json

1Save the endpoint helper scripts and start the endpoints

Paste this whole block:

@'
$v = Get-Content C:\aws-lab\saat-vpc.json | ConvertFrom-Json
$running = aws ec2 describe-vpc-endpoints --filters "Name=tag:lesson,Values=endpoints" "Name=vpc-endpoint-state,Values=pending,available" --query "VpcEndpoints[].VpcEndpointId" --output text
if ($running) { $running -split '\s+' | Set-Content C:\aws-lab\ssm-endpoints.txt; "SSM endpoints already running"; return }
$eps = foreach ($svc in 'ssm','ssmmessages','ec2messages') {
  aws ec2 create-vpc-endpoint --vpc-id $v.VpcId --vpc-endpoint-type Interface --service-name "com.amazonaws.ap-south-1.$svc" --subnet-ids $v.PrivateA --security-group-ids $v.EndpointSg --private-dns-enabled --tag-specifications "ResourceType=vpc-endpoint,Tags=[{Key=Name,Value=saat-$svc-endpoint},{Key=course,Value=saatvedha-aws},{Key=lesson,Value=endpoints}]" --query VpcEndpoint.VpcEndpointId --output text
}
$eps | Set-Content C:\aws-lab\ssm-endpoints.txt
do { Start-Sleep 20; $s = aws ec2 describe-vpc-endpoints --vpc-endpoint-ids $eps --query "VpcEndpoints[].State" --output text } until (($s -split '\s+' | Where-Object { $_ -ne 'available' }).Count -eq 0)
"SSM endpoints ready"
'@ | Set-Content C:\aws-lab\Start-SsmEndpoints.ps1

@'
if (-not (Test-Path C:\aws-lab\ssm-endpoints.txt)) { "SSM endpoints already deleted"; return }
$eps = Get-Content C:\aws-lab\ssm-endpoints.txt
aws ec2 delete-vpc-endpoints --vpc-endpoint-ids $eps | Out-Null
Remove-Item C:\aws-lab\ssm-endpoints.txt
"SSM endpoints deleted"
'@ | Set-Content C:\aws-lab\Stop-SsmEndpoints.ps1

.\Start-SsmEndpoints.ps1

After two to three minutes you should see:

SSM endpoints ready

2Launch data01 and wait for Session Manager

Paste this whole block:

$ami = aws ssm get-parameter --name /aws/service/ami-amazon-linux-latest/al2023-ami-kernel-default-x86_64 --query Parameter.Value --output text
$id = aws ec2 run-instances --image-id $ami --instance-type t3.micro --subnet-id $v.PrivateA --security-group-ids $v.AppSg --iam-instance-profile Name=saat-ec2-ssm-profile --metadata-options HttpTokens=required --tag-specifications 'ResourceType=instance,Tags=[{Key=Name,Value=data01},{Key=course,Value=saatvedha-aws},{Key=lesson,Value=14}]' 'ResourceType=volume,Tags=[{Key=course,Value=saatvedha-aws},{Key=lesson,Value=14}]' --query "Instances[0].InstanceId" --output text
do { Start-Sleep 20; $ping = aws ssm describe-instance-information --filters "Key=InstanceIds,Values=$id" --query "InstanceInformationList[0].PingStatus" --output text } until ($ping -eq 'Online')
"data01 $id is $ping"

3Create and attach a 10 GiB gp3 volume

Paste this whole block:

$vol = aws ec2 create-volume --availability-zone ap-south-1a --size 10 --volume-type gp3 --encrypted --tag-specifications 'ResourceType=volume,Tags=[{Key=Name,Value=data01-data},{Key=course,Value=saatvedha-aws},{Key=lesson,Value=14}]' --query VolumeId --output text
aws ec2 wait volume-available --volume-ids $vol
aws ec2 attach-volume --volume-id $vol --instance-id $id --device /dev/sdf --query State --output text
aws ec2 wait volume-in-use --volume-ids $vol
aws ec2 describe-volumes --volume-ids $vol --query "Volumes[0].[VolumeType,Size,Iops,Throughput,Encrypted]" --output text

You should see something like this:

attaching
gp3     10      3000    125     True

4Format and mount it inside the server

Open a session with aws ssm start-session --target $id, then type this at the sh-5.2$ prompt:

lsblk -l -o NAME,SIZE,MOUNTPOINTS
sudo mkfs -t xfs /dev/nvme1n1
sudo mkdir /data
sudo mount /dev/nvme1n1 /data
echo "UUID=$(sudo blkid -s UUID -o value /dev/nvme1n1) /data xfs defaults,nofail 0 2" | sudo tee -a /etc/fstab
echo "order 1001" | sudo tee /data/orders.txt
df -h /data | tail -1

The last line should show something like this:

/dev/nvme1n1     10G  104M  9.9G   2% /data

Check that nvme1n1 is the 10G disk in the lsblk list before you format it. Formatting the wrong device destroys its data. Leave the session open.

5Take a snapshot

Back in PowerShell, run this:

$snap = aws ec2 create-snapshot --volume-id $vol --description "data01-data before resize" --tag-specifications 'ResourceType=snapshot,Tags=[{Key=course,Value=saatvedha-aws},{Key=lesson,Value=14}]' --query SnapshotId --output text
aws ec2 wait snapshot-completed --snapshot-ids $snap
aws ec2 describe-snapshots --snapshot-ids $snap --query "Snapshots[0].[SnapshotId,State,VolumeSize]" --output text

You should see something like this:

snap-0c1d2e3f4a5b60718   completed       10

6Grow the volume to 20 GiB while it runs

Run this:

aws ec2 modify-volume --volume-id $vol --size 20 --query "VolumeModification.ModificationState" --output text
do { Start-Sleep 10; $st = aws ec2 describe-volumes-modifications --volume-ids $vol --query "VolumesModifications[0].ModificationState" --output text } until ($st -in 'optimizing','completed')
$st

You should see this:

modifying
optimizing

In the session, grow the file system:

lsblk -l -o NAME,SIZE,MOUNTPOINTS
df -h /data | tail -1
sudo xfs_growfs /data | tail -1
df -h /data | tail -1
cat /data/orders.txt

You should see something like this:

NAME         SIZE MOUNTPOINTS
nvme0n1        8G
nvme0n1p1      8G /
nvme0n1p127    1M
nvme0n1p128   10M /boot/efi
nvme1n1       20G /data
/dev/nvme1n1     10G  104M  9.9G   2% /data
data blocks changed from 2621440 to 5242880
/dev/nvme1n1     20G  176M   20G   1% /data
order 1001

The disk showed 20G as soon as AWS reached optimizing, but the file system stayed at 10G until xfs_growfs. Your file was never touched.

7Compare gp2 and gp3 for different sizes

Back in PowerShell, paste this whole block:

foreach ($gib in 20, 100, 1000, 4000) {
  [pscustomobject]@{ SizeGiB = $gib; Gp2Iops = [math]::Max(100, [math]::Min(16000, 3 * $gib)); Gp3IncludedIops = 3000 }
} | Format-Table

You should see this:

SizeGiB Gp2Iops Gp3IncludedIops
------- ------- ---------------
     20     100            3000
    100     300            3000
   1000    3000            3000
   4000   12000            3000

Small gp2 disks are slow unless they burst. gp3 gives 3,000 IOPS at any size, and you add more only when a big disk needs it.

✅ Checkpoint: data01 has a 20 GiB gp3 data disk mounted at /data with orders.txt intact, and a completed snapshot from before the resize. Keep everything for the break lab.