Monitoring Block Storage for VPC health states, volume status, and metrics
By using the UI, CLI, or API, you can check on the status and health states of your Block Storage for VPC volumes. You can also view the cumulative number of read and write operations for a specific volume that is attached to a virtual server instance.
Monitoring Block Storage for VPC performance
You can monitor certain Block Storage for VPC volume performance from the VPC virtual server instance metrics. These metrics include:
-
Cumulative number of bytes read for a volume since the virtual server instance was started.
-
Cumulative number of bytes written for a volume since the virtual server instance was started.
To see these metrics in the UI, do the following.
- In the IBM Cloud console, go to Infrastructure > Compute > Virtual server instances.
- Click the instance name to go to the instance details.
- Click the Monitoring tab and scroll to the Volume metrics.
- Select a volume. The read and write metrics are displayed. Figure 1 shows this view.
Block Storage volume status
The following table shows the statuses that you might see when you create, view, or manage your Block Storage for VPC volumes, and the associated health state.
Status | Meaning | Health state |
---|---|---|
Available | A volume is available and can be attached to an instance. An attached data volume is available. A boot volume is available. |
OK |
Failed | A volume creation failed. | Inapplicable |
Pending | A volume is being created. | Inapplicable |
Pending deletion | A volume is being deleted. When you're unsure if the volume is deleted, verify this state. Attempting to delete a volume again while in this state results in a conflict error. | Inapplicable |
Updating | A volume's capacity is expanding or volume IOPS being adjusted. | OK |
Unusable | A volume is unusable because the customer root key (CRK) was deleted or disabled. | Inapplicable |
Block Storage volume health states
Volume health states correspond with volume statuses. Table 2 describes the health states and health reasons.
Health State | Reason |
---|---|
OK | A volume is performing at the expected I/O performance and capacity is sufficient. No network connection issues are present. Or the volume was restored from a snapshot (hydration is completed). |
Degraded |
A volume is experiencing degraded performance for any of the following reasons:
|
Inapplicable | The volume is being created. The volume creation failed. The volume is pending, pending deletion, or unusable. No health reasons are reported. |
Faulted | The volume is unreachable, inoperative, or entirely incapacitated. |
For more information about the health states and reason codes in the API, see the API reference for creating, listing, and updating volumes.
Volume performance when you restore from a snapshot
Boot and data volume performance is initially degraded when you restore them from a snapshot. During the restoration, your data is copied from IBM Cloud® Object Storage to Block Storage for VPC. After the restoration process is complete, full IOPS can be realized on the new volume.
Restoring a boot volume from a "bootable" snapshot and then provisioning an instance with it results in slower performance because the restored boot volume is not yet fully hydrated (that is, fully provisioned). Performance is slower than creating an instance from a regular boot volume.