Block Volumes for Roving Edge Infrastructure

Describes how to manage block volume tasks, including creating, updating, and deleting block volumes, on your Roving Edge Infrastructure devices.

You can perform the following block volume tasks:

The Block Volume service does not reserve storage space for block volumes and boot volumes in advance. Instead, storage space is consumed when the data is written to the block volume. For example, if a 100 GB block volume is created, it does not mean that 100 GB is reserved from the total available storage space for this block volume. The storage space remains available to all services and can be exhausted before the 100 GB volume is filled with data.

Also, the Block Volume service does not validate the specified size of a created block volume against the available storage space. This lack of validation can lead to over subscription when the total size of created volumes exceeds the storage space available on the device. Do not rely on block volume sizes to calculate storage space utilization. Instead, follow the information about storage space usage displayed in the Device Console's Monitoring page.

See Overview of Block Volume in the Oracle Cloud Infrastructure documentation for more information on this service.

Using Logical Volume Management

If logical volume management (LVM) is enabled on a Roving Edge Infrastructure device, any disk failure can result in the whole or partial storage system being unavailable. The device can tolerate up to two disk failures and still function. The blockstorage-backend service, blockstorage-imaging service and rover-object-gateway service can continue to function after one or two disks are faulty. The system should continue working in degraded state.

If the LVM volume type is configured for Data Protection, all block volumes and instances are still accessible. For other volume types, data loss can occur because some block volumes and instance virtual machines might not be accessible. Those impacted block and boot volumes are identified as FAULTY and you must delete them. After the system has detected that one or two disks have been lost, the faulty disks are removed from the LVM group and cannot be added back later if the disks are recovered by itself. Any data on those disks cannot be recovered and is lost.

You must detach or delete FAULTY block volume and boot volumes, otherwise block storage backplane and imaging services are in the "Unavailable" state and you cannot create new block and boot volumes.

Boot images do not display the FAULTY indicator if a failure occurs. Instead, the boot image's lifecycle states are identified as "Unknown" in the Device Console and UNKNOWN_ENUM_VALUE in the CLI returns.