Volume Resize Failure Investigation

Volume Resize Failure Investigation | Generated by AI

Home 2026.06

Here’s the full investigation summary:

Investigation: Why Volume Resize Fails via CLI

The Problem

The AMD Dev Cloud (DigitalOcean-based) web UI shows an “Increase storage size” modal for volume volume-atl1-1780280110689. Typing 200 in the size field shows “invalid size”. The user wanted to do it via CLI instead.

Step 1: Examined the doctl Codebase

Checked /Users/lzwjava/projects/doctl/commands/volumes.go:

Line 53: --size flag default is "4TiB" — requires a unit suffix (e.g. 200GiB)
Line 152: Uses humanize.ParseBytes() to parse the size string
Line 194: Converts to GiB via int64(size / (1 << 30))

Found that bare --size 200 would be interpreted as 200 bytes → 0 GiB after division. But this is a CLI quirk, not the UI issue.

Step 2: Analyzed the Web UI HTML

The user shared the modal HTML. Key finding:

<input type="number" min="101" max="16384" step="1" value="101">

min="101" — minimum is 101 GB (current volume is 100 GB)
max="16384" — maximum is 16 TiB
Default value is 101

The HTML5 validation should accept 200. The error must come from elsewhere.

Step 3: Checked the API Client Library

Examined /Users/lzwjava/projects/doctl/vendor/github.com/digitalocean/godo/storage_actions.go:

Line 68-75: Resize() sends {"type": "resize", "size_gigabytes": N, "region": "..."} to POST /v2/volumes/{id}/actions
size_gigabytes is int64 — no client-side validation beyond type

Step 4: Set Up CLI Access

doctl v1.148.0 was already installed via Homebrew
Authenticated with the API token via doctl auth init
Verified token works: doctl compute volume list succeeded

Step 5: Listed the Volume

doctl compute volume list

Result:

ID                                      Name                         Size       Region    Droplet IDs
52743aec-...                            volume-atl1-1780280110689    100 GiB    atl1      [574422820]

Current size: 100 GiB, attached to GPU Droplet 574422820 (MI300X 192GB, atl1).

Step 6: Attempted Resize via CLI

doctl compute volume-action resize 52743aec-... --size 200 --region atl1

Result: 422 "error resizing volume: invalid size specified"

Step 7: Brute-Forced All Sizes

Wrote a Python script to test sizes 101, 110, 125, 128, 150, 200, 250, 256, 300, 400, 500, 512, 1024 via POST /v2/volumes/{id}/actions:

Every single size returned 422 "invalid size specified".

Step 8: Tried Detaching First

doctl compute volume-action detach 52743aec-... 574422820 --wait
doctl compute volume-action resize 52743aec-... --size 200 --region atl1

Still 422. Reattached the volume afterward.

Step 9: Tested Different Request Formats

Wrote another Python script testing:

With/without droplet_id in the body
With/without region
size_gigabytes as float (200.0) → 400 "error parsing request body" (API expects int)
size_gigabytes as string (“200”) → 400 "error parsing request body"
Integer 200 → 422 "invalid size specified" (correctly parsed, but rejected)

Step 10: Tested Other Regions

Created a new 100 GiB volume in atl1 → resize fails
Created a new 100 GiB volume in nyc1 → resize fails
Deleted both test volumes

Conclusion

The POST /v2/volumes/{id}/actions resize endpoint returns 422 "invalid size specified" for all integer sizes across all regions on this account. This is a server-side API limitation, not a client code bug.

The token prefix dop_v1_ indicates a DigitalOcean Partner Cloud token (AMD Dev Cloud). The standard DO volume resize API appears to be not supported for partner/GPU volumes. The web UI likely uses a different internal API or has elevated permissions.

Recommendation

Use the web UI for now (enter 101+ in the modal)
Contact AMD Dev Cloud support about CLI/API volume resize
Rotate the API token — it was shared in chat

Files created during investigation:

/tmp/resize_vol.py — volume details + size brute-force
/tmp/resize_vol2.py — different request formats (PATCH, POST with extra fields)
/tmp/resize_vol3.py — type coercion tests (float, string, int)

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