Preparing to take a snapshot

Virtual Storage Platform One SDS Block Storage Administrator Guide

Version

1.17.x

Audience

anonymous

Part Number

MK-24VSP1SDS002-04

Run either of the following commands with the copy-source volume specified to create a volume (S-VOL) to take a snapshot of.

To prepare to take a snapshot, the following calculation results must be less than 80.

usedCapacity [MiB] / allocatableCapacity [MiB] × 100

You can verify the usedCapacity and allocatableCapacity by running either of the following commands:

REST API: GET /v1/objects/storage-controllers

CLI: storage_controller_list
Preparation for taking a snapshot cannot be performed if there is a snapshot whose status is "Deleting" or "Error" on the copy-source volume.
If the copy-source volume is a snapshot, the system can be prepared for taking a snapshot only when the copy-source snapshot is in Normal state.
When universalReplicatorAttribute is "P-VOL", you can prepare for obtaining snapshots regardless of the Universal Replicator pair status. When universalReplicatorAttribute is "S-VOL", you can prepare for obtaining snapshots provided that the Universal Replicator pair status is "PAIR", "SSUS", or "PSUE." If the Universal Replicator pair status is "COPY", preparing for obtaining snapshots is unavailable. Also, it is not possible to prepare for obtaining snapshots for the volumes whose volumeType is "Journal" or "FormerJournal."

Note:

Preparing to take a snapshot and taking a snapshot can be performed in one step. Batch processing simplifies the operation, but if the snapshot is to be taken after I/O is stopped, the I/O stop time will be longer because I/O must also be stopped for the time it takes to prepare to take the snapshot.

Therefore, this document separately describes the operation for preparing to take a snapshot and the operation for taking a snapshot.

To sequentially perform the operation for preparing to take a snapshot and the operation for taking a snapshot, specify PrepareAndFinalize for the operationType parameter (in the case of CLI, --operation_type) when you perform step 4.

Note that the operation for preparing to take a snapshot and the operation for taking a snapshot are sequentially performed if the operationType parameter (in the case of CLI, --operation_type) is omitted.

Required role: Storage
When preparing for obtaining snapshots for volumes in a VPS: Scope of the VPS

When you are not using the multi-tenancy function or when you are using the multi-tenancy function and you prepare obtaining snapshots for volumes in a system scope, you can skip this task. Go to the next step.

When you prepare obtaining snapshots for volumes in a VPS, verify the VPS ID and conditions set for the VPS (QoS settings).

If you want to specify a VPS by its name in the CLI, verify the VPS name.

REST API: GET /v1/objects/virtual-private-storages

CLI: vps_list

Note:
A system administrator can make QoS settings for individual volumes without limitation for the QoS settings of volumes. If QoS parameters are not specified, volumes (S-VOL) for obtaining snapshots are created with the QoS parameters set to a VPS.
Verify the ID of the volume for which you want to create a snapshot.

If you want to specify a volume by its name in the CLI, verify the name of the intended volume.

REST API: GET /v1/objects/volumes

CLI: volume_list
Obtain a list of S-VOL information by specifying the ID of the copy-source volume, and then confirm that there are no volumes for which "snapshotStatus" is "Deleting" or "Error."

If you use the CLI, you can specify the name of the volume instead of its ID.

REST API: GET /v1/objects/volumes/<id>/snapshot-volumes

CLI: snapshot_volume_list

If there are any volumes with snapshotStatus of "Deleting", wait for the respective processes to complete. If there are any volumes with "Error" snapshotStatus, delete the associated S-VOLs.
Prepare to take a snapshot.

Run either of the following commands with the ID of the copy-source volume specified and "Prepare" specified for the operationType parameter.

If you use the CLI, you can specify the name of the volume instead of its ID. The parameter is --operation_type and the specified value is "Prepare."

REST API: POST /v1/objects/volumes/actions/create-snapshot/invoke

CLI: volume_create_snapshot

Verify the job ID which is displayed after the command is run.
Verify the state of the job.

Run either of the following commands with the job ID specified.

REST API: GET /v1/objects/jobs/<jobId>

CLI: job_show

If the job state is "Succeeded", the job is completed.
Obtain a list of S-VOL information to verify that an S-VOL whose snapshot status is "Prepared" has been created.

Run one of the following commands with the ID of the copy-source volume specified.

If you use the CLI, you can specify a name instead of the ID of the volume.

REST API: GET /v1/objects/volumes/<id>/snapshot-volumes

CLI: snapshot_volume_list

After performing step 5, it might take approximately one minute for the snapshot status to change. When you want to verify that the snapshot status has changed, wait for approximately one minute before verification.