diff --git a/tools/lib/filereader.py b/tools/lib/filereader.py
index 1db3207e4b..af3dc5e658 100644
--- a/tools/lib/filereader.py
+++ b/tools/lib/filereader.py
@@ -1,9 +1,21 @@
 import os
+import socket
+from urllib.parse import urlparse
 
 from openpilot.tools.lib.url_file import URLFile
 
 DATA_ENDPOINT = os.getenv("DATA_ENDPOINT", "http://data-raw.comma.internal/")
 
+def internal_source_available():
+  try:
+    hostname = urlparse(DATA_ENDPOINT).hostname
+    if hostname:
+      socket.gethostbyname(hostname)
+      return True
+  except socket.gaierror:
+    pass
+  return False
+
 def resolve_name(fn):
   if fn.startswith("cd:/"):
     return fn.replace("cd:/", DATA_ENDPOINT)
diff --git a/tools/lib/logreader.py b/tools/lib/logreader.py
index decffccd66..4d76f2a38f 100755
--- a/tools/lib/logreader.py
+++ b/tools/lib/logreader.py
@@ -20,7 +20,7 @@ from cereal import log as capnp_log
 from openpilot.common.swaglog import cloudlog
 from openpilot.tools.lib.comma_car_segments import get_url as get_comma_segments_url
 from openpilot.tools.lib.openpilotci import get_url
-from openpilot.tools.lib.filereader import FileReader, file_exists
+from openpilot.tools.lib.filereader import FileReader, file_exists, internal_source_available
 from openpilot.tools.lib.helpers import RE
 from openpilot.tools.lib.route import Route, SegmentRange
 
@@ -143,6 +143,9 @@ def comma_api_source(sr: SegmentRange, mode: ReadMode):
   return apply_strategy(mode, rlog_paths, qlog_paths, valid_file=valid_file)
 
 def internal_source(sr: SegmentRange, mode: ReadMode):
+  if not internal_source_available():
+    raise Exception("Internal source not available")
+
   segs = parse_slice(sr)
 
   def get_internal_url(sr: SegmentRange, seg, file):