Amazon EBS volume status checks

Volume status checks enable you to better understand, track, and manage potential inconsistencies in the data on an Amazon EBS volume. They are designed to provide you with the information that you need to determine whether your Amazon EBS volumes are impaired, and to help you control how a potentially inconsistent volume is handled.

Volume status checks are automated tests that run every 5 minutes and return a pass or fail status. If all checks pass, the status of the volume is ok. If a check fails, the status of the volume is impaired. If the status is insufficient-data, the checks may still be in progress on the volume. You can view the results of volume status checks to identify any impaired volumes and take any necessary actions.

When Amazon EBS determines that a volume's data is potentially inconsistent, the default is that it disables I/O to the volume from any attached EC2 instances, which helps to prevent data corruption. After I/O is disabled, the next volume status check fails, and the volume status is impaired. In addition, you'll see an event that lets you know that I/O is disabled, and that you can resolve the impaired status of the volume by enabling I/O to the volume. We wait until you enable I/O to give you the opportunity to decide whether to continue to let your instances use the volume, or to run a consistency check using a command, such as fsck (Linux instances) or chkdsk (Windows instances), before doing so.

If the consistency of a particular volume is not a concern, and you'd prefer that the volume be made available immediately if it's impaired, you can override the default behavior by configuring the volume to automatically enable I/O. If you enable the Auto-Enable IO volume attribute (autoEnableIO in the API), the volume status check continues to pass. In addition, you'll see an event that lets you know that the volume was determined to be potentially inconsistent, but that its I/O was automatically enabled. This enables you to check the volume's consistency or replace it at a later time.

The I/O performance status check compares actual volume performance to the expected performance of a volume. It alerts you if the volume is performing below expectations. This status check is available only for Provisioned IOPS SSD (io1 and io2) and General Purpose SSD (gp3) volumes that are attached to an instance. The status check is not valid for General Purpose SSD (gp2), Throughput Optimized HDD (st1), Cold HDD (sc1), or Magnetic(standard) volumes. The I/O performance status check is performed once every minute, and CloudWatch collects this data every 5 minutes. It might take up to 5 minutes from the moment that you attach an io1 or io2 volume to an instance for the status check to report the I/O performance status.

The following table lists statuses for Amazon EBS volumes.

You can view and work with status checks using the following methods.