vtl-appliance/dist/adastra-vtl-installer/docs/WEB_UI_CONFIG_LOADER_FIX.md

🔄 Web UI Config Loader Fix

📋 Issue

Web UI was not loading existing configuration from /etc/mhvtl/device.conf on page load. Instead, it always showed hardcoded default values (STK L700, XYZZY_A, etc.), forcing users to manually reconfigure everything even when a valid config already existed.

❌ Previous Behavior

On Page Load:

• Always showed default values:
  • Vendor: STK
  • Product: L700
  • Serial: XYZZY_A
  • 4 default drives with IBM ULT3580-TD5/TD6

User Experience:

• Had to manually re-enter all existing configuration
• No way to see current server configuration
• Risk of overwriting working config with defaults

---

✅ Fix Applied

New Behavior

On Page Load:

1. ✅ Fetches existing device.conf from server via API
2. ✅ Parses the configuration file
3. ✅ Populates all form fields with actual values
4. ✅ Loads all existing drives with correct settings
5. ✅ Falls back to defaults only if no config exists

Implementation

1. Updated Page Load Sequence

Before:

document.addEventListener('DOMContentLoaded', function () {
    initNavigation();
    addDefaultDrives();      // ❌ Always use defaults
    generateConfig();
});

After:

document.addEventListener('DOMContentLoaded', function () {
    initNavigation();
    loadExistingConfig();    // ✅ Load from server first
});

2. Added loadExistingConfig() Function

Fetches configuration from server:

function loadExistingConfig() {
    fetch('api.php', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ action: 'load_config' })
    })
    .then(response => response.json())
    .then(data => {
        if (data.success && data.config) {
            parseAndLoadConfig(data.config);  // Parse and populate
        } else {
            addDefaultDrives();  // Fallback to defaults
            generateConfig();
        }
    })
    .catch(error => {
        console.error('Error loading config:', error);
        addDefaultDrives();  // Fallback on error
        generateConfig();
    });
}

3. Added parseAndLoadConfig() Function

Comprehensive parser that extracts:

Library Configuration:

• Library ID, Channel, Target, LUN
• Vendor, Product, Serial Number
• NAA, Home Directory, Backoff

Drive Configuration:

• Drive Number, Channel, Target, LUN
• Library ID, Slot Number
• Vendor, Product, Serial Number
• NAA, Compression settings, Backoff

Parsing Logic:

function parseAndLoadConfig(configText) {
    const lines = configText.split('\n');
    let libraryData = {};
    let drivesData = [];
    
    // Parse line by line
    for (let line of lines) {
        if (line.startsWith('Library:')) {
            // Extract: Library: 10 CHANNEL: 00 TARGET: 00 LUN: 00
            const match = line.match(/Library:\s+(\d+)\s+CHANNEL:\s+(\d+)...
        }
        else if (line.startsWith('Drive:')) {
            // Extract: Drive: 11 CHANNEL: 00 TARGET: 01 LUN: 00
            const match = line.match(/Drive:\s+(\d+)\s+CHANNEL:\s+(\d+)...
        }
        else if (line.includes('Vendor identification:')) {
            // Extract vendor name
        }
        // ... more parsing logic
    }
    
    // Populate UI fields
    document.getElementById('lib-vendor').value = libraryData.vendor;
    // ... populate all fields
    
    // Recreate drives
    drivesData.forEach(driveData => {
        const drive = { /* mapped data */ };
        drives.push(drive);
        renderDrive(drive);
    });
}

4. Added findDriveType() Helper

Maps vendor/product to drive type dropdown:

function findDriveType(vendor, product) {
    for (const [key, value] of Object.entries(driveTypes)) {
        if (value.vendor === vendor && value.product === product) {
            return key;  // e.g., 'IBM ULT3580-TD8'
        }
    }
    return 'IBM ULT3580-TD8';  // Default fallback
}

---

🎯 Features

1. Smart Loading

• Loads existing config if available
• Falls back to defaults if no config exists
• Handles errors gracefully

2. Complete Parsing

• Parses all library settings
• Parses all drive configurations
• Maintains MHVTL drive ID convention (11, 12, 13, 14)

3. Accurate Mapping

• Maps vendor/product to correct drive types
• Preserves all compression settings
• Maintains NAA and serial numbers

4. User-Friendly

• Shows actual current configuration
• No need to re-enter existing settings
• Can modify and save changes easily

---

📊 Example

Current Configuration on Server

VERSION: 5

Library: 10 CHANNEL: 00 TARGET: 00 LUN: 00
 Vendor identification: ADASTRA
 Product identification: HEPHAESTUS-V
 Unit serial number: HPV00001
 NAA: 10:22:33:44:ab:cd:ef:00
 Home directory: /opt/mhvtl
 Backoff: 400

Drive: 11 CHANNEL: 00 TARGET: 01 LUN: 00
 Library ID: 10 Slot: 01
 Vendor identification: IBM
 Product identification: ULT3580-TD8
 Unit serial number: XYZZY_A1
 NAA: 10:22:33:44:ab:cd:ef:01
 Compression: factor 3 enabled 1
 Compression type: lzo
 Backoff: 400

Drive: 12 CHANNEL: 00 TARGET: 02 LUN: 00
 Library ID: 10 Slot: 02
 Vendor identification: HP
 Product identification: Ultrium 6-SCSI
 Unit serial number: XYZZY_A2
 ...

Web UI Now Shows

Library Tab:

• Library ID: 10
• Vendor: ADASTRA
• Product: HEPHAESTUS-V
• Serial: HPV00001
• NAA: 10:22:33:44:ab:cd:ef:00
• Home Directory: /opt/mhvtl
• Backoff: 400

Drives Tab:

• Drive 11 (IBM ULT3580-TD8)

  • Channel: 0, Target: 1, LUN: 0
  • Library ID: 10, Slot: 1
  • Serial: XYZZY_A1

• Drive 12 (HP Ultrium 6-SCSI)

  • Channel: 0, Target: 2, LUN: 0
  • Library ID: 10, Slot: 2
  • Serial: XYZZY_A2

---

🔄 Workflow

Before Fix:

1. User opens web UI
2. Sees default values (STK L700)
3. Has to manually configure everything
4. Risk of losing existing config

After Fix:

1. User opens web UI ✅
2. Sees actual current configuration ✅
3. Can modify if needed ✅
4. Or just review current settings ✅

---

📁 Files Modified

1. /builder/adastra-vtl/web-ui/script.js

   • Updated DOMContentLoaded event handler
   • Added loadExistingConfig() function
   • Added parseAndLoadConfig() function
   • Added findDriveType() helper function

2. /var/www/html/mhvtl-config/script.js

   • Deployed updated version to web server

---

🧪 Testing

Test Case 1: Existing Configuration

Setup: Valid device.conf exists at /etc/mhvtl/device.conf

Expected:

• Web UI loads all values from config
• Library settings match file
• All drives displayed correctly
• Drive IDs follow MHVTL convention (11, 12, 13, 14)

Test Case 2: No Configuration

Setup: No device.conf file exists

Expected:

• Web UI falls back to defaults
• Shows 4 default drives
• User can configure from scratch

Test Case 3: API Error

Setup: API endpoint fails or returns error

Expected:

• Web UI catches error gracefully
• Falls back to defaults
• Error logged to console
• User can still use the UI

---

🎉 Benefits

1. Time Saving - No need to re-enter existing configuration
2. Accuracy - Shows actual current state of the system
3. Safety - Less risk of accidentally overwriting working config
4. Convenience - Can review settings without SSH access
5. Professional - Behaves like a proper configuration manager

---

🔗 Related Fixes

This fix complements the previous fixes:

1. Drive ID Convention Fix - Ensures correct drive numbering (11, 12, 13, 14)
2. Library Detection Fix - Fixed vtllibrary startup issues
3. Web UI Drive ID Fix - Fixed config generation

All three fixes work together to provide a complete, working solution.

---

Status: ✅ FIXED
Date: December 9, 2025
Tested On: Ubuntu 24.04.3 LTS
Web Server: Apache 2.4
Access URL: http://localhost/mhvtl-config/