fixing iscsi mapping for library

internal/httpapp/routes.go

@@ -176,6 +176,10 @@ func (a *App) routes() {
 		func(w http.ResponseWriter, r *http.Request) { a.handleListVTLMediaChangers(w, r) },
 		nil, nil, nil, nil,
 	))
+	a.mux.HandleFunc("/api/v1/vtl/devices/iscsi", methodHandler(
+		func(w http.ResponseWriter, r *http.Request) { a.handleListVTLDevicesForISCSI(w, r) },
+		nil, nil, nil, nil,
+	))
 	a.mux.HandleFunc("/api/v1/vtl/changer/status", methodHandler(
 		func(w http.ResponseWriter, r *http.Request) { a.handleGetVTLMediaChangerStatus(w, r) },
 		nil, nil, nil, nil,

internal/httpapp/vtl_handlers.go

@@ -285,3 +285,42 @@ func (a *App) handleEjectTape(w http.ResponseWriter, r *http.Request) {
 		"drive_id": fmt.Sprintf("%d", req.DriveID),
 	})
 }
+
+// handleListVTLDevicesForISCSI returns all tape devices (drives and medium changers) for iSCSI passthrough
+func (a *App) handleListVTLDevicesForISCSI(w http.ResponseWriter, r *http.Request) {
+	devices := []map[string]interface{}{}
+
+	// Get drives
+	drives, err := a.vtlService.ListDrives()
+	if err == nil {
+		for _, drive := range drives {
+			devices = append(devices, map[string]interface{}{
+				"type":        "drive",
+				"device":      drive.Device,
+				"id":          drive.ID,
+				"library_id":  drive.LibraryID,
+				"vendor":      drive.Vendor,
+				"product":     drive.Product,
+				"description": fmt.Sprintf("Tape Drive %d (Library %d) - %s %s", drive.ID, drive.LibraryID, drive.Vendor, drive.Product),
+			})
+		}
+	}
+
+	// Get medium changers
+	changers, err := a.vtlService.ListMediaChangers()
+	if err == nil {
+		for _, changer := range changers {
+			devices = append(devices, map[string]interface{}{
+				"type":        "changer",
+				"device":      changer.Device,
+				"id":          changer.ID,
+				"library_id":  changer.LibraryID,
+				"slots":       changer.Slots,
+				"drives":      changer.Drives,
+				"description": fmt.Sprintf("Media Changer (Library %d) - %d slots, %d drives", changer.LibraryID, changer.Slots, changer.Drives),
+			})
+		}
+	}
+
+	writeJSON(w, http.StatusOK, devices)
+}

web/templates/iscsi.html

@@ -85,13 +85,17 @@
 
 <!-- Add LUN Modal -->
 <div id="add-lun-modal" class="hidden fixed inset-0 bg-black/50 flex items-center justify-center z-50">
-  <div class="bg-slate-800 rounded-lg border border-slate-700 p-6 max-w-md w-full mx-4">
+  <div class="bg-slate-800 rounded-lg border border-slate-700 p-6 max-w-md w-full mx-4 max-h-[90vh] overflow-y-auto">
     <h3 class="text-xl font-semibold text-white mb-4">Add LUN to Target</h3>
     <form id="add-lun-form" onsubmit="addLUN(event)" class="space-y-4">
       <input type="hidden" name="target_id" id="lun-target-id">
+      <input type="hidden" name="target_type" id="lun-target-type" value="disk">
+      
+      <!-- Disk Mode: Storage Volume -->
+      <div id="lun-disk-mode" class="space-y-4">
         <div>
           <label class="block text-sm font-medium text-slate-300 mb-1">Select Storage Volume</label>
-        <select name="zvol" id="lun-zvol-select" required class="w-full px-3 py-2 bg-slate-900 border border-slate-700 rounded text-white text-sm focus:outline-none focus:ring-2 focus:ring-blue-600">
+          <select name="zvol" id="lun-zvol-select" class="w-full px-3 py-2 bg-slate-900 border border-slate-700 rounded text-white text-sm focus:outline-none focus:ring-2 focus:ring-blue-600">
             <option value="">Loading volumes...</option>
           </select>
           <p class="text-xs text-slate-400 mt-1">Or enter manually below</p>
@@ -100,6 +104,24 @@
           <label class="block text-sm font-medium text-slate-300 mb-1">Or Enter Volume Name Manually</label>
           <input type="text" name="zvol-manual" id="lun-zvol-manual" placeholder="pool/zvol" class="w-full px-3 py-2 bg-slate-900 border border-slate-700 rounded text-white text-sm focus:outline-none focus:ring-2 focus:ring-blue-600">
         </div>
+      </div>
+      
+      <!-- Tape Mode: Tape Devices -->
+      <div id="lun-tape-mode" class="space-y-4 hidden">
+        <div>
+          <label class="block text-sm font-medium text-slate-300 mb-1">Select Tape Device</label>
+          <select name="device" id="lun-device-select" class="w-full px-3 py-2 bg-slate-900 border border-slate-700 rounded text-white text-sm focus:outline-none focus:ring-2 focus:ring-blue-600">
+            <option value="">Loading devices...</option>
+          </select>
+          <p class="text-xs text-slate-400 mt-1">Physical medium changer or tape drive device</p>
+        </div>
+        <div>
+          <label class="block text-sm font-medium text-slate-300 mb-1">Or Enter Device Path Manually</label>
+          <input type="text" name="device-manual" id="lun-device-manual" placeholder="/dev/sg0 or /dev/st0" class="w-full px-3 py-2 bg-slate-900 border border-slate-700 rounded text-white text-sm focus:outline-none focus:ring-2 focus:ring-blue-600">
+          <p class="text-xs text-slate-400 mt-1">Medium changer: /dev/sg* | Tape drive: /dev/st* or /dev/nst*</p>
+        </div>
+      </div>
+      
       <div class="flex gap-2 justify-end">
         <button type="button" onclick="closeModal('add-lun-modal')" class="px-4 py-2 bg-slate-700 hover:bg-slate-600 text-white rounded text-sm">
           Cancel
@@ -212,10 +234,10 @@ async function loadISCSITargets(type = 'disk') {
                     <div class="flex items-center justify-between text-sm">
                       <div class="flex items-center gap-2">
                         <span class="text-slate-400">LUN ${lun.id}:</span>
-                        <span class="text-slate-300 font-mono">${lun.zvol}</span>
+                        <span class="text-slate-300 font-mono">${lun.zvol || lun.device || 'N/A'}</span>
                       </div>
                       <div class="flex items-center gap-2">
-                        <span class="text-slate-300">${formatBytes(lun.size)}</span>
+                        ${lun.size > 0 ? `<span class="text-slate-300">${formatBytes(lun.size)}</span>` : ''}
                         <button onclick="removeLUN('${target.id}', ${lun.id})" class="ml-2 px-2 py-1 bg-red-600 hover:bg-red-700 text-white rounded text-xs" title="Remove LUN">
                           Remove
                         </button>
@@ -281,12 +303,38 @@ function showCreateISCSIModal(type = 'disk') {
   document.getElementById('create-iscsi-modal').classList.remove('hidden');
 }
 
-async function showAddLUNModal(targetId) {
+async function showAddLUNModal(targetId, targetType) {
   document.getElementById('lun-target-id').value = targetId;
-  document.getElementById('add-lun-modal').classList.remove('hidden');
   
-  // Load available storage volumes
+  // Use provided target type, or fallback to current tab
+  const type = targetType || (currentTab === 'tape' ? 'tape' : 'disk');
+  document.getElementById('lun-target-type').value = type;
+  
+  // Show/hide appropriate sections
+  const diskMode = document.getElementById('lun-disk-mode');
+  const tapeMode = document.getElementById('lun-tape-mode');
+  const zvolSelect = document.getElementById('lun-zvol-select');
+  const deviceSelect = document.getElementById('lun-device-select');
+  
+  if (targetType === 'tape') {
+    diskMode.classList.add('hidden');
+    tapeMode.classList.remove('hidden');
+    zvolSelect.removeAttribute('required');
+    deviceSelect.setAttribute('required', 'required');
+    
+    // Load tape devices
+    await loadTapeDevicesForLUN();
+  } else {
+    diskMode.classList.remove('hidden');
+    tapeMode.classList.add('hidden');
+    zvolSelect.setAttribute('required', 'required');
+    deviceSelect.removeAttribute('required');
+    
+    // Load storage volumes
     await loadZVOLsForLUN();
+  }
+  
+  document.getElementById('add-lun-modal').classList.remove('hidden');
 }
 
 async function loadZVOLsForLUN() {
@@ -339,6 +387,56 @@ async function loadZVOLsForLUN() {
   }
 }
 
+async function loadTapeDevicesForLUN() {
+  try {
+    const res = await fetch('/api/v1/vtl/devices/iscsi', { headers: getAuthHeaders() });
+    const selectEl = document.getElementById('lun-device-select');
+    
+    if (!res.ok) {
+      selectEl.innerHTML = '<option value="">Error loading devices</option>';
+      return;
+    }
+    
+    const devices = await res.json();
+    
+    if (!Array.isArray(devices)) {
+      selectEl.innerHTML = '<option value="">No devices available</option>';
+      return;
+    }
+    
+    if (devices.length === 0) {
+      selectEl.innerHTML = '<option value="">No tape devices found. Make sure mhvtl is running.</option>';
+      return;
+    }
+    
+    // Clear and populate dropdown
+    selectEl.innerHTML = '<option value="">Select a device...</option>';
+    devices.forEach(device => {
+      const option = document.createElement('option');
+      option.value = device.device;
+      option.textContent = device.description || `${device.type}: ${device.device}`;
+      selectEl.appendChild(option);
+    });
+    
+    // Update manual input when dropdown changes
+    selectEl.addEventListener('change', function() {
+      if (this.value) {
+        document.getElementById('lun-device-manual').value = this.value;
+      }
+    });
+    
+    // Update dropdown when manual input changes
+    document.getElementById('lun-device-manual').addEventListener('input', function() {
+      if (this.value && !selectEl.value) {
+        // Allow manual entry even if not in dropdown
+      }
+    });
+  } catch (err) {
+    console.error('Error loading tape devices:', err);
+    document.getElementById('lun-device-select').innerHTML = '<option value="">Error loading devices</option>';
+  }
+}
+
 async function showConnectionInstructions(targetId) {
   try {
     const res = await fetch(`/api/v1/iscsi/targets/${targetId}/connection`, { headers: getAuthHeaders() });
@@ -419,15 +517,27 @@ async function addLUN(e) {
   let requestBody = {};
   
   if (targetType === 'tape') {
-    // Tape mode: use device
+    // Tape mode: use device (medium changer or tape drive)
-    const device = document.getElementById('lun-device-input').value.trim();
+    const deviceSelect = document.getElementById('lun-device-select').value;
+    const deviceManual = document.getElementById('lun-device-manual').value.trim();
+    const device = deviceSelect || deviceManual;
+    
     if (!device) {
-      alert('Please enter a tape device path');
+      alert('Please select or enter a tape device path (e.g., /dev/sg0 for medium changer or /dev/st0 for tape drive)');
       return;
     }
+    
+    // Determine backstore type based on device
+    let backstore = 'pscsi'; // Default for tape devices
+    if (device.startsWith('/dev/sg')) {
+      backstore = 'pscsi'; // Medium changer
+    } else if (device.startsWith('/dev/st') || device.startsWith('/dev/nst')) {
+      backstore = 'pscsi'; // Tape drive
+    }
+    
     requestBody = {
       device: device,
-      backstore: 'pscsi'
+      backstore: backstore
     };
   } else {
     // Disk mode: use ZVOL
@@ -456,7 +566,8 @@ async function addLUN(e) {
       e.target.reset();
       document.getElementById('lun-zvol-select').innerHTML = '<option value="">Loading volumes...</option>';
       document.getElementById('lun-zvol-manual').value = '';
-      document.getElementById('lun-device-input').value = '';
+      document.getElementById('lun-device-select').innerHTML = '<option value="">Loading devices...</option>';
+      document.getElementById('lun-device-manual').value = '';
       // Reload targets for the current tab
       loadISCSITargets(targetType);
       alert('LUN added successfully');