run-aci: Artillery Cloud dashboard shows 0 workers despite successful distributed test execution

[kbalachander]

Description

When running distributed load tests via artillery run-aci, Artillery Cloud dashboard consistently shows 0 workers during and after test execution. All other metrics (response times, status codes, VU counts, per-endpoint breakdowns) are reported correctly. Only the worker count metadata is missing.

Artillery Version: 2.0.29 (latest)

Steps to Reproduce

1. Configure Azure ACI with service principal + storage account
2. Run:

   npx artillery run-aci \
     --count 5 \
     --region uaenorth \
     --record \
     --key "$ARTILLERY_CLOUD_API_KEY" \
     tests/my-test.yml

3. Open the Run URL in Artillery Cloud dashboard

Expected: Dashboard shows 5 workers
Actual: Dashboard shows 0 workers (metrics are correctly aggregated)

Evidence

Three test runs all show 0 workers despite successful completion:

Test	--count	VUs Completed	Workers Shown
Health Check	1	20	0
Broker API	5	16,950	0
Identity API	3	5,130	0

Root Cause Analysis

Investigation of the source code identified two issues:

1. WORKER_ID env var mismatch (lib/platform/az/aci.js + lib/platform/cloud/cloud.js)

The ACI platform sets WORKER_ID_OVERRIDE on containers, but the Cloud plugin checks for WORKER_ID:

// aci.js - sets WORKER_ID_OVERRIDE
{ name: 'WORKER_ID_OVERRIDE', value: workerId }

// cloud.js - checks WORKER_ID
const enabledInCloudWorker =
  typeof process.env.WORKER_ID !== 'undefined' &&
  typeof process.env.ARTILLERY_CLOUD_API_KEY !== 'undefined';

The bash wrapper script (loadgen-worker) converts WORKER_ID_OVERRIDE to WORKER_ID, but this happens after Node.js has already evaluated process.env.WORKER_ID as undefined. Workers never register with Artillery Cloud.

2. Missing worker count in ACI metadata (lib/platform/az/aci.js)

The ACI platform emits metadata without the count field:

// aci.js (lines 355-362) - no count field
const metadata = { region: this.region, platformConfig: { memory, cpu } };

While run.js correctly includes it:

// run.js - includes count
metadata: { count: runnerOpts.count || Number(flags.count), ... }

Suggested Fix

Fix 1: Add WORKER_ID alongside WORKER_ID_OVERRIDE in container env vars:

{ name: 'WORKER_ID', value: workerId }

Fix 2: Include count in ACI metadata:

const metadata = { region: this.region, count: this.count, platformConfig: { memory, cpu } };

Environment

• Node.js: v25.3.0
• OS: Linux (Ubuntu)
• Azure Region: UAE North
• ACI containers provisioned successfully, metrics aggregation works correctly

Related Issues

• Artillery test on Azure ACI failed to conclude #3355 - Artillery test on Azure ACI failed to conclude (related ACI issue)
• ARTILLERY_CLOUD_API_KEY has no effect in .env file #2582 - ARTILLERY_CLOUD_API_KEY has no effect in .env file (related credential handling)

[hassy]

Could you share a specific test id that shows the issue? (here or on hveldstra@artillery.io) We are not aware of any issues that would affect worker count display for tests on Azure.

The finding under (1) is incorrect - it would not affect reporting of worker count. Item (2) - the code in run.js is where the count gets sent (the code in aci.js adds Azure specific metadata later on during the test execution).

[kbalachander]

Hi Hassy, Here is the test I’d: trw58_xkbaqt6xa5rzncqcpwtz5cwnpbcp6_rg5f Thanks and Regards, Balachander K

…

On Thu, 5 Feb 2026 at 14:07 Hassy Veldstra ***@***.***> wrote: *hassy* left a comment (artilleryio/artillery#3691) <#3691 (comment)> Could you share a specific test id that shows the issue? (here or on ***@***.***) We are not aware of any issues that would affect worker count display for tests on Azure. The finding under (1) is incorrect - it would not affect reporting of worker count. Item (2) - the code in run.js is where the count gets sent (the code in aci.js adds Azure specific metadata later on during the test execution). — Reply to this email directly, view it on GitHub <#3691 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AKKFYZ47WKTT3CZR22VPWDD4KMI53AVCNFSM6AAAAACTU2VPWGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTQNJSGQ3TOMZRGI> . You are receiving this because you authored the thread.Message ID: ***@***.***>