diff --git a/dvc/output.py b/dvc/output.py
index 07be26acc..ff0c50a55 100644
--- a/dvc/output.py
+++ b/dvc/output.py
@@ -45,18 +45,24 @@ CHECKSUM_SCHEMA = Any(
     And(Any(str, And(int, Coerce(str))), Length(min=3), Lower),
 )
 
+CASE_SENSITIVE_CHECKSUM_SCHEMA = Any(
+    None,
+    And(str, Length(max=0), SetTo(None)),
+    And(Any(str, And(int, Coerce(str))), Length(min=3)),
+)
+
 # NOTE: currently there are only 3 possible checksum names:
 #
 #    1) md5 (LOCAL, SSH);
-#    2) etag (S3);
+#    2) etag (S3, GS, OSS, AZURE, HTTP);
 #    3) checksum (HDFS);
 #
 # so when a few types of outputs share the same name, we only need
 # specify it once.
 CHECKSUMS_SCHEMA = {
     LocalFileSystem.PARAM_CHECKSUM: CHECKSUM_SCHEMA,
-    S3FileSystem.PARAM_CHECKSUM: CHECKSUM_SCHEMA,
     HDFSFileSystem.PARAM_CHECKSUM: CHECKSUM_SCHEMA,
+    S3FileSystem.PARAM_CHECKSUM: CASE_SENSITIVE_CHECKSUM_SCHEMA,
 }
 
 
diff --git a/tests/func/test_import_url.py b/tests/func/test_import_url.py
index b222ae18f..01ddd172b 100644
--- a/tests/func/test_import_url.py
+++ b/tests/func/test_import_url.py
@@ -123,6 +123,7 @@ def test_import_url_with_no_exec(tmp_dir, dvc, erepo_dir):
     [
         pytest.lazy_fixture("local_cloud"),
         pytest.lazy_fixture("s3"),
+        pytest.lazy_fixture("azure"),
         pytest.param(
             pytest.lazy_fixture("gs"), marks=pytest.mark.needs_internet
         ),