# LOGAR Linux Server Hub

Standalone compiled executable binary distribution for Linux server environments (`Server.bin`).

---

## Overview

`Server.bin` is a self-contained, pre-compiled Linux ELF executable that operates as the central coordination and log analysis hub of the LOGAR telemetry architecture.

### Key Architecture & Capabilities
- **Pre-compiled & Dependency-Free**: Ships as a standalone native Linux ELF binary (`Server.bin`). No Python runtime, pip dependencies, or GnuPG binaries are required on the host system.
- **Authenticated TCP Ingestion Socket (Port 9443)**: Accepts framed OpenPGP encrypted log batches streamed by edge forwarders (`Linux_Client.bin` and `Win_Client.exe`).
- **4-Run Temporal Persistence Rule**: Ingested candidate error signatures are evaluated against an episodic threshold. An anomaly must occur across at least 4 distinct client transmission cycles within a sliding 12-hour evaluation window before promotion from transient noise to a `VERIFIED` anomaly.
- **Embedded Hermes Reporting API (Port 8443)**: Integrated REST API exposing `/api/hermes/report` for external scrapers, SIEM collectors, and alerting dashboards.
- **Pure-Python OpenPGP Cryptography**: Zero dependency on external `gpg` binaries. Automatically generates RSA-2048 encryption keys and SHA-256 fingerprints on first launch.
- **State Database**: Tracks anomaly lifecycles, run counters, and machine telemetry in a local SQLite state database (`logar_state.db`).

---

## 1. Initializing & Generating Server Configuration

### Step 1: Automatic First-Run Generation
When launched without an existing `server_config.json`, `Server.bin` automatically generates:
1. A fresh OpenPGP RSA-2048 encryption keypair (`private_key` and `public_key`).
2. A SHA-256 public encryption fingerprint (`server_fingerprint`).
3. A cryptographically random secret authentication token (`auth_token`).
4. Default network socket coordinates (TCP 9443, Hermes API 8443).

Run `Server.bin` once to initialize:
```bash
./Server.bin
```
Output:
```
[!] Config 'server_config.json' not found. Initializing first-run configuration...
[+] Successfully generated new server config and OpenPGP keypair.
[+] Server Encryption Fingerprint: 375388960531264EA0648EC0D2C4E4ABC6F22AC2
[+] Saved to: server_config.json
```

### Step 2: Configuration Fields Reference
The generated `server_config.json` contains:

```json
{
  "server_name": "LOGAR-Linux-Hub",
  "tcp_host": "0.0.0.0",
  "tcp_port": 9443,
  "hermes_host": "0.0.0.0",
  "hermes_port": 8443,
  "auth_token": "a1b2c3d4e5f67890abcdef1234567890...",
  "db_path": "logar_state.db",
  "evaluation_window_hours": 12,
  "min_persistence_runs": 4,
  "server_fingerprint": "375388960531264EA0648EC0D2C4E4ABC6F22AC2",
  "public_key": "-----BEGIN PGP PUBLIC KEY BLOCK-----\n...",
  "private_key": "-----BEGIN PGP PRIVATE KEY BLOCK-----\n..."
}
```

| Parameter | Default | Description |
| :--- | :--- | :--- |
| `server_name` | `"LOGAR-Linux-Hub"` | Human-readable identifier for this hub instance |
| `tcp_host` | `"0.0.0.0"` | Network interface to bind for edge client TCP ingestion |
| `tcp_port` | `9443` | TCP port for incoming edge log batches |
| `hermes_host` | `"0.0.0.0"` | Network interface to bind for Hermes HTTP API |
| `hermes_port` | `8443` | HTTP port for the Hermes reporting endpoint |
| `auth_token` | *(auto-generated)* | Pre-shared secret required in edge client envelopes |
| `db_path` | `"logar_state.db"` | Path to persistent SQLite issue database |
| `evaluation_window_hours` | `12` | Sliding temporal window for 4-run rule persistence |
| `min_persistence_runs` | `4` | Number of distinct runs required to promote to `VERIFIED` |

---

## 2. Generating Client Configuration Bundles

Edge forwarders (`Linux_Client.bin` and `Win_Client.exe`) require a minimal, anonymous configuration bundle containing socket coordinates, the authentication token, and the server's public key (without sensitive server names or private keys).

Run the following command on the server:
```bash
./Server.bin --create-client-config --server-host <SERVER_PUBLIC_OR_INTERNAL_IP> --server-port 9443 --client-out client_config.json
```

- Replace `<SERVER_PUBLIC_OR_INTERNAL_IP>` with the reachable IP or FQDN of your LOGAR server.
- The output `client_config.json` can be distributed directly to Linux and Windows edge forwarder nodes.

---

## 3. Running Interactively

```bash
./Server.bin --config /path/to/server_config.json
```

### Command-Line Arguments
| Argument | Description |
| :--- | :--- |
| `--config` | Path to server configuration JSON file (default: `server_config.json`) |
| `--create-client-config` | Exports an anonymous client configuration bundle and exits |
| `--server-host` | Hostname/IP to embed in the exported client configuration |
| `--server-port` | Port to embed in the exported client configuration (default: `9443`) |
| `--client-out` | Destination path for exported client configuration (default: `client_config.json`) |

---

## 4. Installing as a Systemd Service (Recommended)

Running `Server.bin` as a native systemd background service ensures continuous execution, automatic restart upon reboot or crash, and centralized log management via `journalctl`.

### Step 1: Create Deployment Directory and User
```bash
# Create dedicated system group and user
sudo useradd --system --no-create-home --shell /usr/sbin/nologin logar

# Prepare deployment folder
sudo mkdir -p /opt/logar-server
sudo cp Server.bin server_config.json /opt/logar-server/
sudo chmod +x /opt/logar-server/Server.bin
sudo chown -R logar:logar /opt/logar-server
```

### Step 2: Create Systemd Service File
Create `/etc/systemd/system/logar-server.service`:

```ini
[Unit]
Description=LOGAR Central Server Hub Service
After=network-online.target
Wants=network-online.target

[Service]
Type=simple
User=logar
Group=logar
WorkingDirectory=/opt/logar-server
ExecStart=/opt/logar-server/Server.bin --config /opt/logar-server/server_config.json
Restart=always
RestartSec=5
LimitNOFILE=65536
StandardOutput=journal
StandardError=journal

[Install]
WantedBy=multi-user.target
```

### Step 3: Enable and Start Service
```bash
sudo systemctl daemon-reload
sudo systemctl enable --now logar-server.service
```

### Step 4: Verify Status and Inspect Logs
```bash
# Check service status
sudo systemctl status logar-server.service

# Stream live server logs
sudo journalctl -u logar-server.service -f
```

---

## 5. Hermes Reporting API & Integration

The server embeds a high-performance HTTP service on port `8443` providing real-time intelligence on promoted anomalies:

### Fetching Promoted Anomalies
```bash
curl -s http://127.0.0.1:8443/api/hermes/report | jq .
```

### Response Schema:
```json
[
  {
    "fingerprint": "prod-web-01.corp.internal:Out_Of_Memory",
    "server": "prod-web-01.corp.internal",
    "signature": "Out_Of_Memory",
    "consecutive_runs": 4,
    "first_seen": "2026-09-04T08:00:00Z",
    "last_seen": "2026-09-04T14:30:00Z",
    "status": "VERIFIED",
    "verified": true,
    "os_type": "linux",
    "sample_message": "kernel: Out of memory: Kill process 1824"
  }
]
```

---

## 6. Firewall Configuration

Ensure the following inbound ports are open on your host firewall:

```bash
# UFW (Ubuntu / Debian)
sudo ufw allow 9443/tcp comment "LOGAR TCP Log Ingestion"
sudo ufw allow 8443/tcp comment "LOGAR Hermes Reporting API"
sudo ufw reload

# Firewalld (RHEL / CentOS / Rocky / Alma)
sudo firewall-cmd --permanent --add-port=9443/tcp
sudo firewall-cmd --permanent --add-port=8443/tcp
sudo firewall-cmd --reload
```