Volcengine IaC Skill

Generate, plan, and apply Volcengine infrastructure with Terraform when the user chooses IaC. volcengine-deploy still owns application packaging, runtime rollout, health checks, and CLI resource-ledger deployment.

When writing new examples, prefer the Cloud Control provider volcengine/volcenginecc. Start from verified examples under assets/examples/, then read the matching references/volcenginecc-*.md note for validation results and pitfalls. Blocked resources are tracked in references/volcenginecc-blocked.md. Existing reusable modules under assets/modules/ still use the legacy volcengine/volcengine provider until each component is re-verified with volcenginecc.

Use this skill when one of these is true:

• the user asks for Terraform or IaC,
• the user already has Terraform state/workspace,
• plan/diff/drift detection matters,
• the infrastructure is intended for long-term team-managed operation and the user chooses IaC,
• the deployment needs VKE, managed databases/cache/storage, load balancers, domains/certificates, IAM/KMS, logging, monitoring, or Serverless triggers and the user chooses IaC.

Do not use this skill just because a deployment is long-lived, VKE-based, or has managed dependencies. Recommend IaC where appropriate, but let the user choose. Do not use this skill when the user asks for CLI, a temporary demo/quick validation, a pure ECS single-VM service with no plan/diff/destroy requirement, or when Terraform/provider installation is blocked and the target can safely use the CLI fallback.

The skill ships verified volcenginecc examples under assets/examples/, legacy reusable modules under assets/modules/, and wrapper scripts for tfvars generation, plan summaries, output export, and drift checks. Select files only after the target shape is known; do not load broad catalogs into context for small Terraform edits.

Resources outside the six legacy modules (CLB/ALB, VKE, CR, databases, caches, object storage) should be added as verified volcenginecc examples first, then wrapped only after repeated use proves the interface is stable.

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0. Prerequisites

Required env vars: VOLCENGINE_ACCESS_KEY, VOLCENGINE_SECRET_KEY, VOLCENGINE_REGION.

Required tools: terraform >= 1.5, jq, git, python3 (for gen_tfvars.py).

Optional: .volcengine/deploy-choice.json from volcengine-prepare/volcengine-deploy. If absent, ask a short batch of Terraform-specific questions.

The skill writes Terraform working files into .volcengine/terraform/ by default. State can use a TOS S3-compatible backend when the user wants remote state; see references/backend-tos.md. Local state is acceptable for small one-off experiments when the user accepts the tradeoff.

If invoked by volcengine-deploy, return outputs in .volcengine/iac-outputs.json and let deploy continue with image build/push, Cloud Assistant commands, Kubernetes manifests, veFaaS release, migrations, and health checks.

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1. Generation Flow

Path A — driven by .volcengine/deploy-choice.json

work_dir="${work_dir:-.volcengine/terraform}"
workload="${workload:-standard}"
mkdir -p "$work_dir"

python3 scripts/gen_tfvars.py \
  --input ".volcengine/deploy-choice.json" \
  --output "$work_dir/terraform.tfvars" \
  --workload "$workload"

gen_tfvars.py derives:

• project, region, AZ pair from the choice file and environment
• enable_vke / enable_cr / enable_rds / enable_redis / enable_tos flags from the chosen mode and known dependencies
• Sizing (instance type, node count, RDS spec, Redis capacity) from a coarse --workload tier

The user can override any value before applying.

Path B — natural language input

When no prepare report exists, ask the user one batch of questions, then create a Terraform working directory from verified examples or legacy modules and generate matching variable values. Required answers:

1. Project name (resource prefix)
2. Region (e.g. cn-beijing)
3. Need VKE? (yes/no)
4. Stateful deps needed: MySQL? PostgreSQL? Redis? TOS bucket?
5. Workload tier: light / standard / heavy

Files written

gen_tfvars.py writes only terraform.tfvars. The Terraform configuration files come from copied verified examples under assets/examples/ or from a small root module assembled from assets/modules/; edit those files to match the selected stack instead of expecting the script to generate them.

File	Purpose
main.tf / variables.tf	Copied or assembled Terraform configuration
terraform.tfvars	Concrete values generated by gen_tfvars.py or edited by hand
backend.tf	Generated only when TOS remote state is selected; otherwise omit it

The full per-module variable schema lives in references/modules.md. For new volcenginecc work, start from a verified example under assets/examples/ instead of these legacy modules unless the user explicitly needs the old provider.

Path C — volcenginecc verified examples

Copy the relevant verified example, then run the same init/validate/plan sequence:

cp -R "assets/examples/<example-name>" "$work_dir/<component>"
cd "$work_dir/<component>"
terraform init -backend=false -input=false
terraform validate
terraform plan -out=tfplan.binary -input=false

Before apply, show the plan summary and require explicit user confirmation. Read the matching reference before changing inputs or destroying resources; the references contain field choices, validation notes, import IDs, and provider pitfalls.

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2. Deployment stack mapping

Use the deployment shape to choose a small set of verified examples. Start with examples; wrap into reusable modules only after repeated use proves the interface stable. Typical stacks combine:

• ECS: volcenginecc-network, volcenginecc-ecs, optional TLS/CloudMonitor
• VKE: volcenginecc-network, volcenginecc-vke, volcenginecc-cr, CLB or ALB
• veFaaS: volcenginecc-vefaas, optional APIG/TLS
• Stateful web app: runtime stack plus RDS, Redis, and/or TOS examples
• Private service: runtime stack plus private NAT or network connectivity examples
• Domain entry: runtime stack plus DNS and load balancer certificate examples

This mapping is a guide, not a promise that a prebuilt module exists. Copy relevant examples into .volcengine/terraform/<component> and keep component boundaries clear so plan/destroy output remains readable.

For the end-to-end VKE private CR nginx path, use assets/examples/volcengine-vke-cr-nginx/ and read references/volcengine-vke-cr-nginx.md first. That example exists for the CR credential addon, core-dns, CR token expiry, and image architecture pitfalls found in a real run.

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3. Catalog

Use the filesystem as the catalog. After selecting a deployment shape, list only the relevant directories under assets/examples/, then read the matching references/volcenginecc-*.md file for validation notes, import IDs, and provider caveats. Do not load every example into context up front.

Common example families:

• volcenginecc-network, VPC extras, NAT, VPN, DirectConnect, CEN, TransitRouter, PrivateLink, DNS, PrivateZone
• volcenginecc-ecs, ECS extras, launch template versions, EBS snapshots, Auto Scaling
• volcenginecc-vke, volcenginecc-cr, CLB/ALB entry, APIG, veFaaS
• volcenginecc-rdsmysql, volcenginecc-rdspostgresql, volcenginecc-rdsmssql, Redis, Kafka allowlist
• volcenginecc-tos, TOS notification, TLS, CloudMonitor, IAM, FileNAS, EFS

Legacy volcengine modules are still available under assets/modules/; read references/modules.md before using them.

Legacy modules currently cover network, vke, cr, rds-mysql, redis, and tos. ECS and CLB/ALB stay as verified examples because their workload shapes vary too much for one stable module interface.

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4. Init & Backend

cd "$work_dir"

# Map Volcengine creds to the Terraform s3 backend's required env variable names.
export AWS_ACCESS_KEY_ID="$VOLCENGINE_ACCESS_KEY"
export AWS_SECRET_ACCESS_KEY="$VOLCENGINE_SECRET_KEY"
export AWS_EC2_METADATA_DISABLED=true

terraform init -input=false
tf_workspace="${tf_workspace:-default}"
terraform workspace select "$tf_workspace" || \
  terraform workspace new "$tf_workspace"

When remote state is requested, generate backend.tf from references/backend-tos.md. The verified TOS backend shape requires skip_requesting_account_id = true and must not set force_path_style or use_path_style.

Provider download (~30–60 seconds first time) goes through registry.terraform.io. In China networks this may be blocked or slow. If public registry access fails and the user still wants IaC, configure Terraform provider_installation with a filesystem or internal mirror. Otherwise return to volcengine-deploy and ask whether to use the CLI resource-ledger path.

For the TOS bucket prerequisite (must exist before init), see references/backend-tos.md. Without a TOS bucket, omit backend.tf and Terraform falls back to local state.

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5. Plan

terraform plan -out=tfplan.binary -input=false
terraform show -json tfplan.binary > tfplan.json
bash scripts/plan_summary.sh tfplan.json

plan_summary.sh groups changes by action (CREATE / UPDATE / DELETE / REPLACE) and prints a one-line summary at the end. Show this to the user before any apply.

Watch for:

• DELETEs you didn't ask for — usually a sign of drift or a mistakenly removed module call
• REPLACEs on stateful resources — RDS / Redis replace = data loss; abort and inspect the diff with terraform show tfplan.binary

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6. Apply

Always require explicit user confirmation. Do not pass -auto-approve. The pattern:

The plan above will create N resources, change M, destroy K. Approve apply? [yes/no]

After yes:

terraform apply tfplan.binary

VKE cluster creation takes ~10–15 minutes. RDS HA instances take ~20 minutes. Surface the long-running message to the user once at apply start so they don't think it hung.

After apply succeeds, run export_outputs.sh automatically:

bash scripts/export_outputs.sh
echo "Resources ready. .volcengine/iac-outputs.json now contains downstream consumption keys."

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7. Outputs for Downstream

export_outputs.sh writes terraform output -json to .volcengine/iac-outputs.json with mode 0600. Downstream skills commonly consume VPC/subnet/security group IDs, VKE kubeconfig, CR repository data, RDS/Redis endpoints or IDs, and TOS bucket names. Some keys are conditional on which examples/modules were enabled; consumers must use defensive jq defaults.

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8. Destroy

# Show what will be destroyed first
terraform plan -destroy -out=destroy.binary
terraform show -json destroy.binary | bash scripts/plan_summary.sh

Then:

This will permanently delete N resources including RDS / Redis / TOS bucket data. Confirm? [yes/no]

On yes:

terraform destroy
# Note: provider does not accept -auto-approve=false; we rely on the agent-level prompt above.

Hard rule: never destroy in prod workspace without a second confirmation. The agent should explicitly re-prompt:

Workspace = prod. Re-confirm destroy by typing 'destroy prod':

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9. Drift Detection

bash scripts/check_drift.sh

Returns:

• 0 and {"drift": false, ...} — no drift
• 2 and {"drift": true, "changed_resources": N, ...} — N resources changed outside Terraform
• 1 and {"drift": "error", ...} — refresh-only plan errored

Use this:

• After known manual interventions (someone resized a node pool via console)
• Periodically as a CI job (weekly)
• Before any non-trivial apply to confirm baseline matches state

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10. Import Existing Resources

If the user wants to adopt resources created via volcengine-cli or console, use terraform import. Import IDs differ by resource; read the matching references/volcenginecc-*.md or references/modules.md before importing. After import, run terraform plan and reconcile by editing config, not state.

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11. Safety Rules

• Never read ~/.volcengine/config.json; it may contain plaintext AK/SK.
• Never commit terraform.tfstate* or .volcengine/iac-outputs.json.
• Never pass -auto-approve to terraform apply or terraform destroy.
• Run check_drift.sh before every apply on shared environments.
• Set mode 0600 on files holding kubeconfig or secrets.
• Pin provider versions in every module/example.

The scripts enforce file permissions where possible. Apply and destroy gates are the agent's responsibility.

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12. Troubleshooting

Look up by the exact error string; act on the mapped cause before suspecting unrelated layers.

Symptom	Cause	Fix
terraform init: "Failed to query available provider packages"	outbound to registry.terraform.io blocked	Configure provider_installation with a filesystem/internal mirror and rerun init; otherwise return to volcengine-deploy and ask whether CLI resource-ledger provisioning is acceptable
terraform init: "InvalidAccessKeyId" against TOS backend	s3 backend env vars not exported	Export AWS_ACCESS_KEY_ID="$VOLCENGINE_ACCESS_KEY", AWS_SECRET_ACCESS_KEY="$VOLCENGINE_SECRET_KEY", AWS_EC2_METADATA_DISABLED=true
terraform init: TOS backend returns InvalidPathAccess	path-style access or unsupported workspace prefix	Use the verified template in references/backend-tos.md: keep skip_requesting_account_id = true, remove force_path_style/use_path_style
apply succeeds for VPC but subnet fails with InvalidVpc.InvalidStatus	VPC not yet Available (consistency window)	Add depends_on = [volcengine_vpc.main] (already wired in the network module)
VKE cluster stuck in Creating for >20 min	quota or AZ capacity	ve vke ListClusters --body '{"Filter":{"Ids":["..."]}}' | jq .Result.Items[0].Status for the real reason
redis output missing endpoint	provider does not export it	Resolve via ve redis DescribeDBInstanceDetail --InstanceId $(jq -r '.redis_instance_id.value' .volcengine/iac-outputs.json)
terraform plan shows unexpected changes after no edits	drift, or provider patch bump silently changing a default	Run check_drift.sh, inspect tfplan.json, decide whether to accept or revert
Two engineers' apply collide	TOS backend has no DynamoDB-style locking	Coordinate manually; see references/backend-tos.md
Resource-specific apply/import drift	provider caveat for that resource	Read the matching references/volcenginecc-*.md note before editing config