-0` | Dynamic | Agent Builder deployment, operator-managed | Inherited |
## Insights and Polly add-on
**Insights/Clio:** No static pods. Deploys lazily as a dynamic LangGraph deployment via the operator on first UI invocation. Reads `insights_encryption_key` from `langsmith-config-secret`. Never rotate this key: it permanently breaks existing Insights data.
**Polly:** Runs as a dynamic LangGraph deployment, operator-managed. Reads `polly_encryption_key` from `langsmith-config-secret`. Same rotation warning as Insights.
## Azure managed services
When `postgres_source = "external"` and `redis_source = "external"` (the recommended production setting), Terraform provisions:
### Azure DB for PostgreSQL Flexible Server
* Holds orgs, users, projects, API keys, settings.
* PostgreSQL ≥ 14 required. The `postgres` module sets `postgres_version` to `14` by default.
* Extensions enabled automatically by the `postgres` module: `btree_gin`, `btree_gist`, `pgcrypto`, `citext`, `pg_trgm`.
* Private VNet only (`subnet-postgres`), SSL port 5432.
* Secret: `langsmith-postgres-secret`, created by the `k8s-bootstrap` Terraform module.
### Azure Managed Redis
* Trace ingestion queue, pub/sub, short-lived cache.
* Azure Managed Redis manages the engine version; there is no version variable to set.
* Each LangSmith installation must use its own dedicated Redis. Shared instances cause deployment tasks to route incorrectly.
* Private VNet only (`subnet-redis`), TLS port 10000.
* Secret: `langsmith-redis-secret`, created by the `k8s-bootstrap` Terraform module.
### Azure Blob Storage
* Trace payloads: large inputs and outputs, attachments.
* Workload Identity (no static keys) via the `k8s-app-identity` Managed Identity.
* Always required. Disabling blob storage breaks the cluster on large payloads.
* Prefixes: `ttl_s/` (14-day TTL), `ttl_l/` (400-day TTL).
### Azure Key Vault
* Centralized secret store for all LangSmith secrets.
* Secret flow: `az keyvault secret show` → `kubectl create secret generic langsmith-config-secret`.
## Workload Identity
Azure AD token exchange happens via the AKS OIDC issuer. Pods access Blob Storage without static keys.
```txt theme={null}
AKS OIDC issuer
→ Federated credential on Azure Managed Identity (one per Kubernetes ServiceAccount)
→ Kubernetes ServiceAccount annotated with azure.workload.identity/client-id
→ Pod labeled with azure.workload.identity/use: "true"
→ Azure AD issues a short-lived token; no storage keys in any Secret or env var
```
Workload Identity is centralized in `modules/k8s-cluster/` alongside the managed identity and OIDC issuer, which avoids circular dependencies and simplifies adding new ServiceAccounts.
### Which pods need Workload Identity
Every pod that reads blob storage env vars must have:
1. A federated credential registered in Terraform (`modules/k8s-cluster/main.tf`).
2. The `azure.workload.identity/use: "true"` label on the Deployment.
3. The `azure.workload.identity/client-id` annotation on the ServiceAccount.
| Pod | Stage | Needs WI |
| - | - | - |
| `langsmith-backend` | Application | Yes |
| `langsmith-platform-backend` | Application | Yes |
| `langsmith-queue` | Application | Yes |
| `langsmith-ingest-queue` | Application | Yes |
| `langsmith-host-backend` | LangSmith Deployment add-on | Yes |
| `langsmith-listener` | LangSmith Deployment add-on | Yes |
| `langsmith-agent-builder-tool-server` | Agent Builder add-on | Yes |
| `langsmith-agent-builder-trigger-server` | Agent Builder add-on | Yes |
| `langsmith-frontend` | Application | No |
| `langsmith-playground` | Application | No |
| `langsmith-ace-backend` | Application | No |
| `langsmith-clickhouse` | Application | No |
| `langsmith-operator` | LangSmith Deployment add-on | No |
All federated credentials are registered in `modules/k8s-cluster/main.tf` under `service_accounts_for_workload_identity`. Adding a new pod that accesses blob storage requires adding its ServiceAccount name to that list and running `terraform apply -target=module.aks`.
If a pod's ServiceAccount has no registered federated credential, Azure AD rejects the token exchange and the pod panics on startup:
```txt theme={null}
panic: blob-storage health-check failed: get container properties failed:
DefaultAzureCredential: failed to acquire a token.
WorkloadIdentityCredential authentication failed.
AADSTS700213: No matching federated identity record found for presented assertion subject
```
## Secret flow
```txt theme={null}
Infrastructure stage
./setup-env.sh (read-only against Key Vault; never writes to KV directly)
First run: prompts for postgres password, license key, admin password, admin email.
Generates api_key_salt, jwt_secret, Fernet keys locally.
Key Vault does not exist yet → writes to local dot-files + secrets.auto.tfvars.
Subsequent: Key Vault exists → reads the six generated secrets (api_key_salt,
jwt_secret, four Fernet keys) from KV. Re-prompts for postgres password,
license key, admin password, and admin email unless LANGSMITH_PG_PASSWORD,
LANGSMITH_LICENSE_KEY, LANGSMITH_ADMIN_PASSWORD, and LANGSMITH_ADMIN_EMAIL
are set. Writes secrets.auto.tfvars. No generation, no KV writes.
Output: secrets.auto.tfvars (gitignored, chmod 600)
Terraform picks this up automatically; no shell session coupling.
terraform apply
Reads: terraform.tfvars (non-sensitive config)
secrets.auto.tfvars (sensitive values; sole input for KV secret creation)
Creates: Azure Key Vault + all secrets as KV secrets (Terraform is the sole KV writer)
Application stage
./setup-env.sh (re-run on any machine; reads generated secrets from Key Vault,
re-prompts for user-provided ones unless LANGSMITH_* env vars are set)
kubectl create secret generic langsmith-config-secret
Reads: Key Vault secrets + Terraform outputs (postgres/redis URLs, blob account)
Writes: K8s secrets: langsmith-config-secret, langsmith-postgres-secret,
langsmith-redis-secret
helm upgrade --install langsmith ...
Chart reads config.existingSecretName = "langsmith-config-secret".
No secrets inline in any YAML file.
```
**Key rule:** `secrets.auto.tfvars` is never committed. Running `./setup-env.sh` on any machine restores it: the generated secrets come from Key Vault, and the user-provided secrets are re-prompted unless supplied through the `LANGSMITH_*` environment variables. Terraform is the sole writer to Key Vault; `setup-env.sh` only reads from it after the first apply.
## Ingress options
| Controller | Variable | DNS label support | Notes |
| - | - | - | - |
| `nginx` *(default)* | `ingress_controller = "nginx"` | Yes | NGINX via Helm, standard Kubernetes Ingress. |
| `istio-addon` | `ingress_controller = "istio-addon"` | Yes | AKS managed Istio service mesh. Use `istio_addon_revision` to pin revision. |
| `istio` | `ingress_controller = "istio"` | Yes | Self-managed Istio via Helm. Full control over revision and config. |
| `agic` | `ingress_controller = "agic"` | Yes | Azure Application Gateway v2 + AKS-managed `ingress_application_gateway` add-on. Native L7 WAF. HTTP-only or dns01 + custom domain. |
| `envoy-gateway` | `ingress_controller = "envoy-gateway"` | Yes | Gateway API native. Uses `envoyproxy/gateway-helm`. |
| `none` | `ingress_controller = "none"` | — | Bring your own ingress. |
Azure Public IP DNS labels (`dns_label`) work with all controllers. `deploy.sh` applies the `service.beta.kubernetes.io/azure-dns-label-name` annotation to the correct LoadBalancer service based on the chosen controller.
For the full TLS compatibility matrix and per-controller setup, see `INGRESS_CONTROLLERS.md` in the [Azure module repo](https://github.com/langchain-ai/terraform/blob/main/modules/azure/INGRESS_CONTROLLERS.md).
## Resource sizing
Four sizing profiles are available.
| Profile | Use case | Set via |
| - | - | - |
| `minimum` | Cost parking, CI smoke tests, single-user demos | `sizing_profile = "minimum"` in `terraform.tfvars` |
| `dev` | Developer use, integration tests, POCs | `sizing_profile = "dev"` |
| `production` | Real traffic, multi-replica + HPA | `sizing_profile = "production"` *(recommended)* |
| `production-large` | \~50 users, \~1000 traces/sec | `sizing_profile = "production-large"` |
### AKS node pools
| Pool | VM Size | vCPU | RAM | Min | Max | Purpose |
| - | - | - | - | - | - | - |
| default | `Standard_D8s_v3` | 8 | 32 GB | 1 | 10 | Core LangSmith, system pods (set min 3 for production) |
| large | `Standard_D16s_v3` | 16 | 64 GB | 0 | 2 | ClickHouse (in-cluster), LGP agent pods |
ClickHouse (when in-cluster) requests 1 to 4 CPU and 2 to 16 GB RAM depending on profile. With [LangChain Managed ClickHouse](/langsmith/langsmith-managed-clickhouse), the `large` pool is only needed for LGP operator-spawned agent pods.
## Optional modules
Each module is count-controlled (`0` disabled, `1` enabled). Enable any combination; the core deployment (Passes 1 to 5) works without them.
| Module | Variable | Use case |
| - | - | - |
| `waf` | `create_waf = true` | Azure WAF policy (OWASP 3.2 + bot protection). Attach to Application Gateway. |
| `diagnostics` | `create_diagnostics = true` | Log Analytics workspace + diagnostic settings for AKS, Key Vault, and PostgreSQL. Recommended for production observability. |
| `bastion` | `create_bastion = true` | Jump VM with a static public IP for private AKS access via `az ssh vm` and Entra ID SSH. |
| `dns` | `create_dns_zone = true` | Azure DNS zone + A record. Required for DNS-01 cert issuance with a custom domain. |
***
[Connect these docs](/use-these-docs) to your agent of choice via MCP for real-time answers.
[Edit this page on GitHub](https://github.com/langchain-ai/docs/edit/main/src/langsmith/self-host-terraform-azure-architecture.mdx) or [file an issue](https://github.com/langchain-ai/docs/issues/new/choose).
| Stage | Layer | What it adds |
| - | - | - |
| Infrastructure | Azure infrastructure | VNet, AKS, Postgres, Redis, Blob, Key Vault, cert-manager, KEDA, ingress controller |
| Application | LangSmith base | frontend, backend, platform-backend, queue, ingest-queue, ace-backend, clickhouse, playground |
| LangSmith Deployment add-on | LangSmith Deployment | host-backend, listener, operator + per-deployment pods |
| Agent Builder add-on | Agent Builder | agent-builder-tool-server, agent-builder-trigger-server + deep-agent LGP |
| Insights + Polly add-on | Insights + Polly | Clio analytics (ClickHouse-backed), Polly eval agent (operator-managed, dynamic) |
## Application deployment paths
| Path | How | When to use |
| - | - | - |
| Helm path | `make init-values && make deploy` | Default. Shell script, interactive, reads TF outputs dynamically. Best for first deploys and day-2 re-deploys. |
| Terraform path | `make init-app && make apply-app` | Declarative. Kubernetes Secrets + `langsmith-ksa` SA + Helm release in Terraform state. Best for GitOps and CI/CD pipelines. |
The Terraform path uses the `app/` module. `make init-app` calls `app/scripts/pull-infra-outputs.sh` to read all infra outputs and write them into `app/infra.auto.tfvars.json`.
## Deployment tiers
### Light deploy (all in-cluster)
```txt theme={null}
AKS Cluster
├── langsmith namespace
│ ├── frontend, backend, platform-backend, playground, queue, ace-backend
│ ├── clickhouse (in-cluster pod)
│ ├── postgres (in-cluster pod)
│ └── redis (in-cluster pod)
├── ingress-nginx (Azure Load Balancer → NGINX)
└── cert-manager (Let's Encrypt TLS)
Azure
├── Azure Blob Storage (trace payloads, always external)
└── Azure Key Vault (secrets)
```
Set in `terraform.tfvars`:
```hcl theme={null}
postgres_source = "in-cluster"
redis_source = "in-cluster"
clickhouse_source = "in-cluster"
```
For the full all-in-cluster walkthrough (NGINX with Let's Encrypt HTTP-01 TLS, all-in-cluster DBs), see `BUILDING_LIGHT_LANGSMITH.md` in the [Azure module repo](https://github.com/langchain-ai/terraform/blob/main/modules/azure/BUILDING_LIGHT_LANGSMITH.md).
### Production (external managed services)
```txt theme={null}
AKS Cluster
├── langsmith namespace
│ ├── frontend, backend, platform-backend, playground, queue, ingest-queue, ace-backend
│ └── clickhouse (in-cluster; use LangChain Managed for production scale)
└── ingress-nginx + cert-manager
Azure Managed Services
├── Azure DB for PostgreSQL Flexible Server (private VNet)
├── Azure Managed Redis (private VNet)
├── Azure Blob Storage (Workload Identity, no static keys)
└── Azure Key Vault
```
## Networking
### Light deploy
```txt theme={null}
langsmith-vnet