diff --git a/app/api/routes/_system.py b/app/api/routes/_system.py
index 3dd31ff..9e6b1f2 100644
--- a/app/api/routes/_system.py
+++ b/app/api/routes/_system.py
@@ -5,6 +5,7 @@ from datetime import datetime
 from base58 import b58encode, b58decode
 from sanic import response
 
+from app.core.models.node_storage import StoredContent
 from app.core._blockchain.ton.platform import platform
 from app.core._crypto.signer import Signer
 from app.core._secrets import hot_pubkey, service_wallet, hot_seed
@@ -18,11 +19,16 @@ def get_git_info():
 
 
 async def s_api_v1_node(request):  # /api/v1/node
+    last_known_index = request.ctx.db_session.query(StoredContent).filter(
+        StoredContent.type == "onchain/content"
+    ).order_by(StoredContent.onchain_index.desc()).first()
+    last_known_index = last_known_index.onchain_index if last_known_index else 0
+    last_known_index = max(last_known_index, 0)
     return response.json({
         'id': b58encode(hot_pubkey).decode(),
         'node_address': service_wallet.address.to_string(1, 1, 1),
         'master_address': platform.address.to_string(1, 1, 1),
-        'indexer_height': 0,
+        'indexer_height': last_known_index,
         'services': {
             service_key: {
                 'status': (service['status'] if (service['timestamp'] and (datetime.now() - service['timestamp']).total_seconds() < 30) else 'not working: timeout'),
diff --git a/app/core/content/content_id.py b/app/core/content/content_id.py
index 43d333c..4ccd9b9 100644
--- a/app/core/content/content_id.py
+++ b/app/core/content/content_id.py
@@ -1,5 +1,4 @@
 from base58 import b58encode, b58decode
-import math
 
 from tonsdk.boc import begin_cell
 from app.core._config import ALLOWED_CONTENT_TYPES
@@ -45,7 +44,10 @@ class ContentId:
         )
         if not (self.safe_onchain_index is None):
             oi_bin_hex = hex(self.safe_onchain_index)[2:]
-            oi_bin_len = math.ceil(len(oi_bin_hex) / 2)
+            if len(oi_bin_hex) % 2:
+                oi_bin_hex = '0' + oi_bin_hex
+
+            oi_bin_len = len(oi_bin_hex) / 2
             cid_bin += b'\xb0' + oi_bin_len.to_bytes(1, 'big') + bytes.fromhex(oi_bin_hex)
         if self.accept_type and include_accept_type:
             at_bin_len = len(self.accept_type.encode())