Volumes

A volume is a network-attached block device, durable independently of any VM. You can:

• Boot a VM from a volume (root_volume) or treat it as additional data storage.
• Detach a volume from one VM and attach it to another.
• Resize while attached (no detach required).
• Snapshot for backup or for stamping out new VMs.

Volumes are zonal — they live in one zone and can only attach to VMs in the same zone. With one zone today (mum-1a) this is implicit.

Create#

exc compute volume create \
  --name app-data \
  --size_gib 100 \
  --baseline_iops 6000 \
  --baseline_throughput_mbps 250

Required: name, size_gib.

Optional: baseline_iops and baseline_throughput_mbps provision guaranteed performance. Omit them and you get the default tier for the size. To stamp a new volume from an existing snapshot, pass --source_snapshot_id <id>.

Attach / detach#

exc compute volume attach --vm_id 42 --volume_id 7
exc compute volume detach --vm_id 42 --volume_id 7

A volume can only be attached to one VM at a time. Detach is safe at any time but won’t quiesce filesystems — unmount inside the guest first.

To list attachments:

exc compute volume attachments --vm_id 42

Resize#

exc compute volume resize --volume_id 7 --new_size_gib 200

Resize works while the volume is attached and the VM is running. Filesystem grow is your responsibility — typically growpart + resize2fs / xfs_growfs inside the guest.

You can only grow, not shrink. You can also bump --baseline_iops and --baseline_throughput_mbps here without changing the size.

Lifecycle#

exc compute volume list
exc compute volume get    --id 7
exc compute volume rename --volume_id 7 --name app-data-v2
exc compute volume delete --volume_id 7

Delete requires the volume to be detached. If it was the root volume of a VM, terminating that VM detaches it automatically (and, by default, deletes it).

Console#

1. Open console.excloud.dev/console/volume.
2. Click Create Volume to create a standalone block volume.
3. Use the volume row actions to inspect, attach, detach, resize, rename, or delete it.

Snapshots#

Take a point-in-time copy with exc compute snapshot create --volume_id 7. Snapshots can be used as the source for a new root volume (--root_volume_source_snapshot_id) — see Snapshots.

Terraform#

The matching resources are excloud_volume and excloud_volume_attachment. Snapshots are excloud_snapshot.