> ## Documentation Index
> Fetch the complete documentation index at: https://docs.kguardian.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Postgres (stateful database)

> Generated NetworkPolicy and seccomp profile for a Postgres pod accepting application traffic

<Warning>
  **Hand-authored illustration.** The YAML on this page illustrates the shape of the policies kguardian generates for this workload — it is not captured generator output. Exact metadata, rule grouping, and selectors produced by `kubectl kguardian gen` will differ. Regeneration of this gallery from a live cluster is planned.
</Warning>

## Workload

A `postgres:16-alpine` StatefulSet running in the `data` namespace. It accepts connections on TCP/5432 from a small set of application pods in the `app` namespace and emits no outbound traffic apart from DNS lookups for cluster-internal hostnames during startup.

## Generated NetworkPolicy

```yaml theme={null}
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: postgres
  namespace: data
  labels:
    kguardian.dev/managed-by: kguardian
    kguardian.dev/version: v1.0.0
spec:
  podSelector:
    matchLabels:
      app: postgres
  policyTypes:
    - Ingress
    - Egress
  ingress:
    - from:
        - namespaceSelector:
            matchLabels:
              kubernetes.io/metadata.name: app
          podSelector:
            matchLabels:
              app.kubernetes.io/name: order-api
        - namespaceSelector:
            matchLabels:
              kubernetes.io/metadata.name: app
          podSelector:
            matchLabels:
              app.kubernetes.io/name: billing-worker
      ports:
        - protocol: TCP
          port: 5432
  egress:
    - to:
        - namespaceSelector:
            matchLabels:
              kubernetes.io/metadata.name: kube-system
          podSelector:
            matchLabels:
              k8s-app: kube-dns
      ports:
        - protocol: UDP
          port: 53
```

## Generated CiliumNetworkPolicy

```yaml theme={null}
apiVersion: cilium.io/v2
kind: CiliumNetworkPolicy
metadata:
  name: postgres
  namespace: data
  labels:
    kguardian.dev/managed-by: kguardian
    kguardian.dev/version: v1.0.0
spec:
  endpointSelector:
    matchLabels:
      app: postgres
  ingress:
    - fromEndpoints:
        - matchLabels:
            app.kubernetes.io/name: order-api
            io.kubernetes.pod.namespace: app
        - matchLabels:
            app.kubernetes.io/name: billing-worker
            io.kubernetes.pod.namespace: app
      toPorts:
        - ports:
            - port: "5432"
              protocol: TCP
  egress:
    - toEndpoints:
        - matchLabels:
            k8s-app: kube-dns
            io.kubernetes.pod.namespace: kube-system
      toPorts:
        - ports:
            - port: "53"
              protocol: UDP
```

## Generated seccomp profile (excerpt)

Full profile contains **162 syscall names**. Representative excerpt:

```json theme={null}
{
  "defaultAction": "SCMP_ACT_ERRNO",
  "architectures": ["SCMP_ARCH_X86_64"],
  "syscalls": [
    {
      "names": [
        "accept", "accept4", "bind", "close", "connect",
        "epoll_create1", "epoll_ctl", "epoll_wait", "fcntl",
        "fdatasync", "fsync", "ftruncate", "getdents64",
        "listen", "lseek", "openat", "pread64", "pwrite64",
        "read", "recvfrom", "rename", "select", "sendto",
        "setsockopt", "socket", "stat", "unlink", "write"
      ],
      "action": "SCMP_ACT_ALLOW"
    },
    {
      "names": [
        "clone", "execve", "futex", "mmap", "mprotect",
        "munmap", "rt_sigaction", "wait4"
      ],
      "action": "SCMP_ACT_ALLOW"
    }
  ]
}
```

## What kguardian observed

Two distinct ingress sources connected to TCP/5432: `order-api` and `billing-worker`, both in the `app` namespace. Egress was limited to UDP/53 lookups during connection establishment (Postgres resolves `pg_hba`-related hostnames at startup). The syscall set is heavier than nginx because Postgres performs heavy I/O: file extension/truncation (`ftruncate`, `pwrite64`, `fdatasync`), directory enumeration (`getdents64`), and process management (`clone`, `wait4`) for its background worker model.