diff --git a/src/modules/content-files/filedb.c b/src/modules/content-files/filedb.c
index 5fa04eda21d0..edecd77f43f5 100644
--- a/src/modules/content-files/filedb.c
+++ b/src/modules/content-files/filedb.c
@@ -87,7 +87,7 @@ int filedb_put (const char *dbpath,
             *errstr = "key name too long for internal buffer";
         return -1;
     }
-    if ((fd = open (path, O_WRONLY | O_CREAT, 0666)) < 0)
+    if ((fd = open (path, O_WRONLY | O_CREAT | O_TRUNC, 0666)) < 0)
         return -1;
     if (write_all (fd, data, size) < 0) {
         ERRNO_SAFE_WRAP (close, fd);
diff --git a/t/t0018-content-files.t b/t/t0018-content-files.t
index 2c6691afba37..bf8a24bb7384 100755
--- a/t/t0018-content-files.t
+++ b/t/t0018-content-files.t
@@ -156,6 +156,26 @@ test_expect_success HAVE_JQ 'kvs-checkpoint.get foo still returns rootref baz' '
         test_cmp rootref3.exp rootref3.out
 '
 
+test_expect_success HAVE_JQ 'kvs-checkpoint.put updates foo rooref with longer rootref' '
+        kvs_checkpoint_put foo abcdefghijklmnopqrstuvwxyz
+'
+
+test_expect_success HAVE_JQ 'kvs-checkpoint.get foo returned rootref with longer rootref' '
+        echo abcdefghijklmnopqrstuvwxyz >rootref3.exp &&
+        kvs_checkpoint_get foo | jq -r .value | jq -r .rootref >rootref3.out &&
+        test_cmp rootref3.exp rootref3.out
+'
+
+test_expect_success HAVE_JQ 'kvs-checkpoint.put updates foo rooref to shorter rootref' '
+        kvs_checkpoint_put foo foobar
+'
+
+test_expect_success HAVE_JQ 'kvs-checkpoint.get foo returned rootref with shorter rootref' '
+        echo foobar >rootref4.exp &&
+        kvs_checkpoint_get foo | jq -r .value | jq -r .rootref >rootref4.out &&
+        test_cmp rootref4.exp rootref4.out
+'
+
 test_expect_success 'load with invalid blobref fails' '
 	test_must_fail backing_load notblobref 2>notblobref.err &&
 	grep "invalid blobref" notblobref.err