EBS Multi-Attach

Amazon EBS Multi-Attach

~ Last updated on : ~ jayendrapatil ~ 1 Comment

EBS Multi-Attach

  • EBS Multi-Attach enables attaching a single Provisioned IOPS SSD (io1 or io2) volume to multiple instances that are in the same AZ.
  • Multiple Multi-Attach enabled volumes can be attached to an instance or set of instances.
  • Each instance to which the volume is attached has full read and write permission to the shared volume.
  • Multi-Attach helps achieve higher application availability in clustered Linux applications that manage concurrent write operations.
  • There are no additional charges for using Amazon EBS Multi-Attach. Standard Provisioned IOPS SSD (io1 and io2) volume charges apply.

io2 Block Express with Multi-Attach

  • io2 Block Express volumes are recommended over io1 for Multi-Attach due to better performance, durability, and feature support.
  • io2 Block Express provides up to 256,000 IOPS, 4,000 MB/s throughput, and 64 TiB capacity per volume.
  • io2 Block Express offers 99.999% durability (100x higher than io1) and consistent sub-millisecond latency.
  • io2 Block Express volumes are now available in all commercial and AWS GovCloud (US) Regions (expanded in 2025).
  • Customers can upgrade from io1 to io2 Block Express without any downtime using the ModifyVolume API.
  • io2 offers up to 4x IOPS and 4x throughput at the same storage price as io1, and up to 50% cheaper IOPS cost for volumes over 32,000 IOPS.

NVMe Reservations (I/O Fencing)

  • Multi-Attach enabled io2 volumes support NVMe reservations, a set of industry-standard storage fencing protocols for data consistency.
  • NVMe reservations enable control and coordination of access from multiple instances to a shared volume.
  • NVMe reservations is enabled by default for all Multi-Attach enabled io2 volumes created after September 18, 2023.
  • For existing io2 volumes created before September 18, 2023, NVMe reservations can be enabled by detaching all instances and then reattaching them.
  • Multi-Attach enabled io1 volumes do not support I/O fencing.
  • Supported NVMe Reservation commands:
    • Reservation Register – registers, unregisters, or replaces a reservation key to associate an instance with a volume.
    • Reservation Acquire – acquires a reservation (Write Exclusive, Exclusive Access, Registrants Only, All Registrants types).
    • Reservation Release – releases or clears a reservation held on a volume.
    • Reservation Report – describes the registration and reservation status of a volume.
  • Supported operating systems for NVMe reservations:
    • Amazon Linux 2 and later
    • RHEL 8.3 and later
    • SUSE Linux Enterprise 12 SP3 and later
    • Windows Server 2016 and later (NVMe driver 1.5.0+)

EBS Multi-Attach Considerations & Limitations

  • Multi-Attach is supported exclusively on Provisioned IOPS SSD volumes (io1 and io2).
  • Multi-Attach enabled volumes can be attached to up to 16 instances built on the Nitro System that are in the same AZ.
  • Linux instances support Multi-Attach enabled io1 and io2 volumes.
  • Windows instances support Multi-Attach enabled io2 volumes only.
  • Multi-Attach for io1 volumes is available in limited Regions only: US East (N. Virginia), US West (Oregon), and Asia Pacific (Seoul). Multi-Attach for io2 is available in all Regions that support io2.
  • io1 volumes with Multi-Attach enabled are not supported with instances built on the Nitro System that support the Scalable Reliable Datagram (SRD) networking protocol only. Use io2 with these instance types.
  • Standard file systems (XFS, EXT4) are not designed to be accessed simultaneously by multiple servers. Use a clustered file system (e.g., GFS2, OCFS2) to ensure data resiliency and reliability for production workloads.
  • Multi-Attach enabled volumes can be attached to one block device mapping per instance.
  • Multi-Attach enabled volumes are deleted on instance termination if the last attached instance is terminated and if that instance is configured to delete the volume on termination.
  • Multi-Attach enabled volumes can’t be created as boot volumes.
  • Multi-Attach can’t be enabled during instance launch using either the EC2 console or RunInstances API.
  • Multi-Attach can’t be enabled or disabled while the volume is attached to an instance.
  • Multi-Attach option is disabled by default.
  • CloudWatch metrics for Multi-Attach volumes are aggregated across all attached instances. Individual instance metrics are not available.

Volume Modification Support

  • io2 Multi-Attach volumes support modifying volume size and provisioned IOPS after creation.
  • io2 Multi-Attach volumes support enabling/disabling Multi-Attach (only while the volume is detached from all instances).
  • io1 Multi-Attach volumes do not support any modifications (size, IOPS, or Multi-Attach state) after creation.
  • Volume type cannot be changed for either io1 or io2 Multi-Attach enabled volumes.

Use Cases

  • Clustered Linux Applications – High availability for applications using clustered file systems like GFS2 or OCFS2.
  • Windows Server Failover Clustering (WSFC) – io2 volumes with NVMe reservations support SQL Server Failover Cluster Instances (FCI) on Windows Server.
  • Amazon EKS Shared Storage – Multi-Attach can share persistent storage across multiple workloads in different EKS clusters within the same AZ.
  • Database High Availability – Enables faster node recovery for clustered databases (e.g., Teradata reported 95% reduction in node recovery time).

AWS Certification Exam Practice Questions

  • Questions are collected from Internet and the answers are marked as per my knowledge and understanding (which might differ with yours).
  • AWS services are updated everyday and both the answers and questions might be outdated soon, so research accordingly.
  • AWS exam questions are not updated to keep up the pace with AWS updates, so even if the underlying feature has changed the question might not be updated
  • Open to further feedback, discussion and correction.
  1. A company runs a clustered database application on multiple EC2 instances within the same Availability Zone. The application requires shared block storage with low latency and high IOPS. The application manages concurrent write operations. Which EBS configuration meets these requirements?
    1. Use a gp3 volume and attach it to multiple instances using Multi-Attach
    2. Use an io2 volume with Multi-Attach enabled and a clustered file system
    3. Use an io1 volume without Multi-Attach and replicate data between instances
    4. Use an EFS file system mounted across all instances

    Answer: 2. Multi-Attach is only supported on Provisioned IOPS SSD volumes (io1/io2). io2 is recommended. A clustered file system is required for concurrent write access.

  2. A company wants to deploy SQL Server Failover Cluster Instances on AWS with shared storage. The solution must provide I/O fencing to prevent data corruption. Which approach should be used?
    1. Use io1 volumes with Multi-Attach enabled
    2. Use io2 volumes with Multi-Attach and NVMe reservations
    3. Use gp3 volumes with Multi-Attach enabled
    4. Use EFS with Windows Server instances

    Answer: 2. io2 volumes with Multi-Attach support NVMe reservations for I/O fencing. io1 does not support I/O fencing. gp3 does not support Multi-Attach. EFS does not support Windows natively for this use case.

  3. Which of the following statements about EBS Multi-Attach are correct? (Choose 3)
    1. Multi-Attach enabled volumes can be attached to instances across multiple AZs
    2. Multi-Attach enabled io2 volumes support NVMe reservations for I/O fencing
    3. Windows instances support Multi-Attach for io2 volumes only
    4. Multi-Attach enabled volumes can be used as boot volumes
    5. io2 Multi-Attach volumes support modification of size and IOPS after creation

    Answer: 2, 3, 5. Multi-Attach is limited to a single AZ. io2 supports NVMe reservations. Windows only supports io2 for Multi-Attach. Multi-Attach volumes cannot be boot volumes. io2 volumes support size and IOPS modifications.

  4. A solutions architect needs to provide shared block storage for a containerized application running on Amazon EKS. Instances are in a single AZ and the application requires high IOPS with consistent low latency. Which storage solution is most appropriate?
    1. Amazon EFS with Provisioned Throughput mode
    2. Amazon FSx for Lustre
    3. EBS io2 Block Express with Multi-Attach via the EBS CSI driver
    4. Instance store volumes shared via NFS

    Answer: 3. EBS io2 Block Express with Multi-Attach provides high IOPS, low latency block storage that can be shared across instances in the same AZ. The EBS CSI driver supports Multi-Attach for EKS workloads.

References

AWS Elastic Block Store Storage – EBS

~ Last updated on : ~ jayendrapatil ~ 61 Comments

EC2 Elastic Block Store – EBS

  • Elastic Block Store – EBS provides highly available, reliable, durable, block-level storage volumes that can be attached to an EC2 instance.
  • EBS as a primary storage device is recommended for data that requires frequent and granular updates e.g. running a database or filesystem.
  • An EBS volume
    • behaves like a raw, unformatted, external block device that can be attached to a single EC2 instance at a time (except with Multi-Attach enabled io1/io2 volumes).
    • persists independently from the running life of an instance.
    • is Zonal and can be attached to any instance within the same Availability Zone and can be used like any other physical hard drive.
    • is particularly well-suited for use as the primary storage for file systems, databases, or any applications that require fine granular updates and access to raw, unformatted, block-level storage.
    • is designed for 99.999% availability and offers 99.999% durability for io2 Block Express volumes (0.001% annual failure rate).

Elastic Block Storage Features

  • EBS Volumes are created in a specific Availability Zone and can be attached to any instance in that same AZ.
  • Volumes can be backed up by creating a snapshot of the volume, which is stored in S3.
  • Volumes can be created from a snapshot that can be attached to another instance within the same region.
  • Volumes can be made available outside of the AZ by creating and restoring the snapshot to a new volume anywhere in that region.
  • Snapshots can also be copied to other regions and then restored to new volumes, making it easier to leverage multiple AWS regions for geographical expansion, data center migration, and disaster recovery.
  • Volumes allow encryption using the EBS encryption feature. All data stored at rest, disk I/O, and snapshots created from the volume are encrypted.
  • Encryption occurs on the EC2 instance, providing encryption of data-in-transit from EC2 to the EBS volume.
  • Elastic Volumes help easily adapt the volumes as the needs of the applications change. Elastic Volumes allow you to dynamically increase capacity, tune performance, and change the type of any new or existing current generation volume with no downtime or performance impact.
  • You can dynamically increase size, modify the provisioned IOPS capacity, and change volume type on live production volumes.
  • EBS now supports up to four Elastic Volumes modifications per volume within a rolling 24-hour window (previously required a 6-hour cooldown between modifications). A new modification can be initiated as soon as the previous one completes.
  • General Purpose SSD (gp3) volumes support up to 80,000 IOPS and 2,000 MiB/s of throughput with up to 64 TiB capacity (increased from 16,000 IOPS, 1,000 MiB/s, and 16 TiB in September 2025).
  • Provisioned IOPS SSD (io2 Block Express) volumes support up to 256,000 IOPS and 4,000 MB/s of throughput with up to 64 TiB capacity and sub-millisecond latency.

EBS Benefits

  • Data Availability
    • Data is automatically replicated in an Availability Zone to prevent data loss due to the failure of any single hardware component.
    • io2 Block Express volumes are designed for 99.999% durability (0.001% annual failure rate), while other volume types provide 99.8%-99.9% durability.
  • Data Persistence
    • persists independently of the running life of an EC2 instance
    • persists when an instance is stopped, started, or rebooted
    • Root volume is deleted, by default, on Instance termination but the behaviour can be changed using the DeleteOnTermination flag
    • All attached volumes persist, by default, on instance termination
  • Data Encryption
    • can be encrypted by the EBS encryption feature
    • uses 256-bit AES-256 and an Amazon-managed key infrastructure.
    • Encryption occurs on the server that hosts the EC2 instance, providing encryption of data-in-transit from the EC2 instance to EBS storage
    • Snapshots of encrypted EBS volumes are automatically encrypted.
    • EBS encryption by default can be enabled at the account level per region, so all new volumes created are automatically encrypted.
  • Snapshots
    • provides the ability to create snapshots (backups) of any EBS volume and write a copy of the data in the volume to S3, where it is stored redundantly in multiple Availability Zones.
    • can be used to create new volumes, increase the size of the volumes or replicate data across Availability Zones or Regions.
    • are incremental backups and store only the data that was changed from the time the last snapshot was taken.
    • Snapshot size can probably be smaller than the volume size as the data is compressed before being saved to S3.
    • Even though snapshots are saved incrementally, the snapshot deletion process is designed so that you need to retain only the most recent snapshot in order to restore the volume.

EBS Volume Types

Refer blog post @ EBS Volume Types

EBS Volume

EBS Volume Creation

  • Creating New volumes
    • Completely new from console or command line tools and can then be attached to an EC2 instance in the same Availability Zone.
  • Restore volume from Snapshots
    • Volumes can also be restored from previously created snapshots
    • New volumes created from existing snapshots are loaded lazily in the background.
    • There is no need to wait for all of the data to transfer from S3 to the volume before the attached instance can start accessing the volume and all its data.
    • If the instance accesses the data that hasn’t yet been loaded, the volume immediately downloads the requested data from S3, and continues loading the rest of the data in the background.
    • Volumes restored from encrypted snapshots are always encrypted, by default.
    • Provisioned Rate for Volume Initialization (May 2025) allows specifying an initialization rate (up to 300 MiB/s) to accelerate the transfer of snapshot data to new volumes, ensuring fully performant volumes within a predictable time frame.
  • Volumes can be created and attached to a running EC2 instance by specifying a block device mapping

EBS Volume Clones (Oct 2025)

  • EBS Volume Clones allow creating instant point-in-time copies of EBS volumes within the same Availability Zone with a single API call.
  • Cloned volumes are available within seconds and provide immediate access to data with single-digit millisecond latency.
  • Data is copied lazily in the background without impacting the performance of the source volume.
  • Eliminates the previous multi-step process of taking snapshots and creating volumes from them for same-AZ copies.
  • Useful for quickly setting up test/development environments with production data.

EBS Volume Detachment

  • EBS volumes can be detached from an instance explicitly or by terminating the instance.
  • EBS root volumes can be detached by stopping the instance.
  • EBS data volumes, attached to a running instance, can be detached by unmounting the volume from the instance first.
  • If the volume is detached without being unmounted, it might result in the volume being stuck in a busy state and could possibly damage the file system or the data it contains.
  • EBS volume can be force detached from an instance, using the Force Detach option, but it might lead to data loss or a corrupted file system as the instance does not get an opportunity to flush file system caches or file system metadata.
  • Charges are still incurred for the volume after its detachment

EBS Volume Deletion

  • EBS volume deletion would wipe out its data and the volume can’t be attached to any instance. However, it can be backed up before deletion using EBS snapshots
  • Recycle Bin for EBS Volumes (Nov 2025) allows setting retention periods for deleted volumes. Deleted volumes can be recovered within the retention period with all attributes (tags, permissions, encryption status) preserved.

EBS Volume Resize

  • EBS Elastic Volumes can be modified to increase the volume size, change the volume type, or adjust the performance of your EBS volumes.
  • If the instance supports Elastic Volumes, changes can be performed without detaching the volume or restarting the instance.
  • Volumes can be modified up to four times within a rolling 24-hour window (enhanced Jan 2026, previously limited to one modification with a 6-hour cooldown).

EBS Volume Snapshots

Refer blog post @ EBS Snapshot

EBS Snapshot Lock

  • EBS Snapshot Lock (Nov 2023) enables locking snapshots to protect them from inadvertent or malicious deletions for compliance and data retention requirements.
  • Snapshots can be locked for a duration ranging from 1 day to approximately 100 years.
  • Supports WORM (Write Once Read Many) compliance requirements.
  • Locked snapshots cannot be deleted until the lock duration expires.
  • No additional cost for locking snapshots.

EBS Snapshots Archive

  • EBS Snapshots Archive provides a low-cost storage tier for long-term retention of rarely-accessed snapshots.
  • Up to 75% lower cost compared to standard snapshot storage.
  • Archived snapshots can be restored when needed (restoration takes 24-72 hours).
  • Amazon Data Lifecycle Manager can automate archival and retention policies.

Recycle Bin for Snapshots

  • Recycle Bin enables restoration of accidentally deleted EBS Snapshots and EBS-backed AMIs.
  • Supports customized delete protection with exclusion tags (Nov 2024) to exclude non-critical resources.
  • Supports CloudFormation for managing Recycle Bin rules (Nov 2024).
  • Supports IPv6 endpoints (Dec 2024).
  • Now also supports EBS Volumes (Nov 2025) in addition to snapshots and AMIs.

EBS Encryption

  • EBS volumes can be created and attached to a supported instance type and support the following types of data
    • Data at rest
    • All disk I/O i.e All data moving between the volume and the instance
    • All snapshots created from the volume
    • All volumes created from those snapshots
  • Encryption occurs on the servers that host EC2 instances, providing encryption of data-in-transit from EC2 instances to EBS storage.
  • EBS encryption is supported with all EBS volume types (gp3, gp2, io2, io1, st1, and sc1), and has the same IOPS performance on encrypted volumes as with unencrypted volumes, with a minimal effect on latency
  • EBS encryption is available on all current generation instance types and select previous generation types.
  • Volumes created from encrypted snapshots and snapshots of encrypted volumes are automatically encrypted using the same encryption key.
  • EBS encryption uses AWS KMS keys (formerly called customer master keys/CMK) when creating encrypted volumes and any snapshots created from the encrypted volumes.
  • EBS volumes can be encrypted using either
    • the AWS managed key (aws/ebs) created for you automatically in each region.
    • a customer managed key that you created separately using AWS KMS, giving you more flexibility, including the ability to create, rotate, disable, define access controls, and audit the encryption keys used to protect your data.
  • Encryption by default can be enabled at the account level per region. When enabled, all new EBS volumes and snapshot copies are automatically encrypted.
  • Public or shared snapshots of encrypted volumes are not supported, because other accounts would be able to decrypt your data and needs to be migrated to an unencrypted status before sharing.
  • Existing unencrypted volumes cannot be encrypted directly, but can be migrated by
    • Option 1
      • create an unencrypted snapshot from the volume
      • create an encrypted copy of an unencrypted snapshot
      • create an encrypted volume from the encrypted snapshot
    • Option 2
      • create an unencrypted snapshot from the volume
      • create an encrypted volume from an unencrypted snapshot (selecting encryption during volume creation)
  • An encrypted snapshot can be created from an unencrypted snapshot by creating an encrypted copy of the unencrypted snapshot.
  • Unencrypted volume cannot be created from an encrypted volume directly but needs to be migrated

EBS Multi-Attach

  • EBS Multi-Attach allows attaching a single Provisioned IOPS SSD (io1 or io2) volume to up to 16 Nitro System-based EC2 instances within the same Availability Zone.
  • All attached instances have full read and write access to the shared volume.
  • io2 Block Express volumes support NVMe reservations for I/O fencing, enabling shared storage with proper coordination between instances (enabled by default for io2 volumes created after Sept 18, 2023).
  • Multi-Attach can be enabled for io2 volumes after creation (if not attached to any instances). For io1, it must be enabled at creation time.
  • Requires a cluster-aware file system (not standard XFS or EXT4) for data resiliency in production.

Refer blog Post @ EBS Multi-Attach

EBS Performance

Refer blog Post @ EBS Performance

EBS vs Instance Store

Refer blog post @ EBS vs Instance Store

AWS Certification Exam Practice Questions

  • Questions are collected from Internet and the answers are marked as per my knowledge and understanding (which might differ with yours).
  • AWS services are updated everyday and both the answers and questions might be outdated soon, so research accordingly.
  • AWS exam questions are not updated to keep up the pace with AWS updates, so even if the underlying feature has changed the question might not be updated
  • Open to further feedback, discussion and correction.
  1. _____ is a durable, block-level storage volume that you can attach to a single, running Amazon EC2 instance.
    1. Amazon S3
    2. Amazon EBS
    3. None of these
    4. All of these
  2. Which Amazon storage do you think is the best for my database-style applications that frequently encounter many random reads and writes across the dataset?
    1. None of these.
    2. Amazon Instance Storage
    3. Any of these
    4. Amazon EBS
  3. What does Amazon EBS stand for?
    1. Elastic Block Storage
    2. Elastic Business Server
    3. Elastic Blade Server
    4. Elastic Block Store
  4. Which Amazon Storage behaves like raw, unformatted, external block devices that you can attach to your instances?
    1. None of these.
    2. Amazon Instance Storage
    3. Amazon EBS
    4. All of these
  5. A user has created numerous EBS volumes. What is the general limit for each AWS account for the maximum number of EBS volumes that can be created?
    1. 10000
    2. 5000
    3. 100
    4. 1000
  6. Select the correct set of steps for exposing the snapshot only to specific AWS accounts
    1. Select Public for all the accounts and check mark those accounts with whom you want to expose the snapshots and click save.
    2. Select Private and enter the IDs of those AWS accounts, and click Save.
    3. Select Public, enter the IDs of those AWS accounts, and click Save.
    4. Select Public, mark the IDs of those AWS accounts as private, and click Save.
  7. If an Amazon EBS volume is the root device of an instance, can I detach it without stopping the instance?
    1. Yes but only if Windows instance
    2. No
    3. Yes
    4. Yes but only if a Linux instance
  8. Can we attach an EBS volume to more than one EC2 instance at the same time?
    1. Yes, with Multi-Attach enabled io1/io2 volumes to up to 16 Nitro-based instances in the same AZ
    2. No
    3. Only EC2-optimized EBS volumes.
    4. Only in read mode.

    Note: This answer has been updated. EBS Multi-Attach (available since 2020) allows io1/io2 volumes to be attached to up to 16 Nitro-based instances simultaneously within the same AZ.

  9. Do the Amazon EBS volumes persist independently from the running life of an Amazon EC2 instance?
    1. Only if instructed to when created
    2. Yes
    3. No
  10. Can I delete a snapshot of the root device of an EBS volume used by a registered AMI?
    1. Only via API
    2. Only via Console
    3. Yes
    4. No
  11. By default, EBS volumes that are created and attached to an instance at launch are deleted when that instance is terminated. You can modify this behavior by changing the value of the flag_____ to false when you launch the instance
    1. DeleteOnTermination
    2. RemoveOnDeletion
    3. RemoveOnTermination
    4. TerminateOnDeletion
  12. Your company policies require encryption of sensitive data at rest. You are considering the possible options for protecting data while storing it at rest on an EBS data volume, attached to an EC2 instance. Which of these options would allow you to encrypt your data at rest? (Choose 3 answers)
    1. Implement third party volume encryption tools
    2. Do nothing as EBS volumes are encrypted by default
    3. Encrypt data inside your applications before storing it on EBS
    4. Encrypt data using native data encryption drivers at the file system level
    5. Implement SSL/TLS for all services running on the server
  13. Which of the following are true regarding encrypted Amazon Elastic Block Store (EBS) volumes? Choose 2 answers
    1. Supported on all Amazon EBS volume types
    2. Snapshots are automatically encrypted
    3. Available to all instance types
    4. Existing volumes can be encrypted
    5. Shared volumes can be encrypted
  14. How can you secure data at rest on an EBS volume?
    1. Encrypt the volume using the S3 server-side encryption service
    2. Attach the volume to an instance using EC2’s SSL interface.
    3. Create an IAM policy that restricts read and write access to the volume.
    4. Write the data randomly instead of sequentially.
    5. Use an encrypted file system on top of the EBS volume
  15. A user has deployed an application on an EBS backed EC2 instance. For a better performance of application, it requires dedicated EC2 to EBS traffic. How can the user achieve this?
    1. Launch the EC2 instance as EBS dedicated with PIOPS EBS
    2. Launch the EC2 instance as EBS enhanced with PIOPS EBS
    3. Launch the EC2 instance as EBS dedicated with PIOPS EBS
    4. Launch the EC2 instance as EBS optimized with PIOPS EBS
  16. A user is trying to launch an EBS backed EC2 instance under free usage. The user wants to achieve encryption of the EBS volume. How can the user encrypt the data at rest?
    1. Use AWS EBS encryption to encrypt the data at rest (EBS encryption is supported on all current generation instance types including t2/t3 micro)
    2. User cannot use EBS encryption and has to encrypt the data manually or using a third party tool
    3. The user has to select the encryption enabled flag while launching the EC2 instance
    4. Encryption of volume is not available as a part of the free usage tier
  17. A user is planning to schedule a backup for an EBS volume. The user wants security of the snapshot data. How can the user achieve data encryption with a snapshot?
    1. Use encrypted EBS volumes so that the snapshot will be encrypted by AWS
    2. While creating a snapshot select the snapshot with encryption
    3. By default the snapshot is encrypted by AWS
    4. Enable server side encryption for the snapshot using S3
  18. A user has launched an EBS backed EC2 instance. The user has rebooted the instance. Which of the below mentioned statements is not true with respect to the reboot action?
    1. The private and public address remains the same
    2. The Elastic IP remains associated with the instance
    3. The volume is preserved
    4. The instance runs on a new host computer
  19. A user has launched an EBS backed EC2 instance. What will be the difference while performing the restart or stop/start options on that instance?
    1. For restart it does not charge for an extra hour, while every stop/start it will be charged as a separate hour
    2. Every restart is charged by AWS as a separate hour, while multiple start/stop actions during a single hour will be counted as a single hour
    3. For every restart or start/stop it will be charged as a separate hour
    4. For restart it charges extra only once, while for every stop/start it will be charged as a separate hour
  20. A user has launched an EBS backed instance. The user started the instance at 9 AM in the morning. Between 9 AM to 10 AM, the user is testing some script. Thus, he stopped the instance twice and restarted it. In the same hour the user rebooted the instance once. For how many instance hours will AWS charge the user?
    1. 3 hours
    2. 4 hours
    3. 2 hours
    4. 1 hour
  21. You are running a database on an EC2 instance, with the data stored on Elastic Block Store (EBS) for persistence At times throughout the day, you are seeing large variance in the response times of the database queries Looking into the instance with the isolate command you see a lot of wait time on the disk volume that the database’s data is stored on. What two ways can you improve the performance of the database’s storage while maintaining the current persistence of the data? Choose 2 answers
    1. Move to an SSD backed instance
    2. Move the database to an EBS-Optimized Instance
    3. Use Provisioned IOPs EBS
    4. Use the ephemeral storage on an m2.4xLarge Instance Instead
  22. An organization wants to move to Cloud. They are looking for a secure encrypted database storage option. Which of the below mentioned AWS functionalities helps them to achieve this?
    1. AWS MFA with EBS
    2. AWS EBS encryption
    3. Multi-tier encryption with Redshift
    4. AWS S3 server-side storage
  23. A user has stored data on an encrypted EBS volume. The user wants to share the data with his friend’s AWS account. How can user achieve this?
    1. Create an AMI from the volume and share the AMI
    2. Copy the data to an unencrypted volume and then share
    3. Take a snapshot and share the snapshot with a friend
    4. If both the accounts are using the same encryption key then the user can share the volume directly
  24. A user is using an EBS backed instance. Which of the below mentioned statements is true?
    1. The user will be charged for volume and instance only when the instance is running
    2. The user will be charged for the volume even if the instance is stopped
    3. The user will be charged only for the instance running cost
    4. The user will not be charged for the volume if the instance is stopped
  25. A user is planning to use EBS for his DB requirement. The user already has an EC2 instance running in the VPC private subnet. How can the user attach the EBS volume to a running instance?
    1. The user must create EBS within the same VPC and then attach it to a running instance.
    2. The user can create EBS in the same zone as the subnet of instance and attach that EBS to instance. (Should be in the same AZ)
    3. It is not possible to attach an EBS to an instance running in VPC until the instance is stopped.
    4. The user can specify the same subnet while creating EBS and then attach it to a running instance.
  26. A user is creating an EBS volume. He asks for your advice. Which advice mentioned below should you not give to the user for creating an EBS volume?
    1. Take the snapshot of the volume when the instance is stopped
    2. Stripe multiple volumes attached to the same instance
    3. Create an AMI from the attached volume (AMI is created from the snapshot)
    4. Attach multiple volumes to the same instance
  27. An EC2 instance has one additional EBS volume attached to it. How can a user attach the same volume to another running instance in the same AZ?
    1. Terminate the first instance and only then attach to the new instance
    2. Attach the volume as read only to the second instance
    3. Detach the volume first and attach to new instance
    4. No need to detach. Just select the volume and attach it to the new instance, it will take care of mapping internally
  28. What is the scope of an EBS volume?
    1. VPC
    2. Region
    3. Placement Group
    4. Availability Zone

Additional Practice Questions (Updated 2025-2026)

  1. A company wants to create instant copies of their EBS volumes for testing purposes within the same Availability Zone without using snapshots. Which feature should they use?
    1. EBS Fast Snapshot Restore
    2. EBS Snapshot Copy
    3. EBS Volume Clones
    4. EBS Multi-Attach
  2. Which EBS volume type provides sub-millisecond latency, up to 256,000 IOPS, and 99.999% durability?
    1. gp3
    2. io1
    3. io2 Block Express
    4. gp2
  3. A company needs to protect their EBS snapshots from accidental or malicious deletion to meet regulatory compliance requirements. Which feature should they use?
    1. EBS Encryption
    2. Recycle Bin
    3. AWS Backup
    4. EBS Snapshot Lock
  4. What is the maximum size, IOPS, and throughput for a gp3 volume as of September 2025?
    1. 16 TiB, 16,000 IOPS, 1,000 MiB/s
    2. 64 TiB, 64,000 IOPS, 4,000 MiB/s
    3. 64 TiB, 80,000 IOPS, 2,000 MiB/s
    4. 32 TiB, 32,000 IOPS, 2,000 MiB/s
  5. A team needs to accelerate the initialization of hundreds of EBS volumes from snapshots for a large-scale deployment. Which feature ensures predictable initialization times?
    1. EBS Fast Snapshot Restore
    2. Provisioned Rate for Volume Initialization
    3. EBS Volume Clones
    4. EBS Elastic Volumes
  6. How many times can you modify an EBS volume within a rolling 24-hour window? (as of Jan 2026)
    1. 1 time with 6-hour cooldown
    2. 2 times
    3. 4 times
    4. Unlimited
  7. Which of the following statements about EBS Multi-Attach is correct? (Choose 2)
    1. Multi-Attach is supported on io1 and io2 Provisioned IOPS volumes
    2. Multi-Attach allows attachment to instances across multiple Availability Zones
    3. Multi-Attach enabled volumes can be attached to up to 16 Nitro-based instances
    4. Multi-Attach is supported on gp3 volumes

Reference

Amazon EBS User Guide