diff --git a/cmake/AddFdbTest.cmake b/cmake/AddFdbTest.cmake
index 3835f82350e..4bd4656805a 100644
--- a/cmake/AddFdbTest.cmake
+++ b/cmake/AddFdbTest.cmake
@@ -84,13 +84,13 @@ function(add_fdb_test)
   if (NOT "${ADD_FDB_TEST_TEST_NAME}" STREQUAL "")
     set(test_name ${ADD_FDB_TEST_TEST_NAME})
   endif()
-  math(EXPR test_idx "${CURRENT_TEST_INDEX} + 1")
+  math(EXPR test_idx "${CURRENT_TEST_INDEX} + ${NUM_TEST_FILES}")
   set(CURRENT_TEST_INDEX "${test_idx}" PARENT_SCOPE)
   # set(<var> <value> PARENT_SCOPE) doesn't set the
   # value in this scope (only in the parent scope). So
   # if the value was undefined before, it will still be
   # undefined.
-  math(EXPR assigned_id "${test_idx} - 1")
+  math(EXPR assigned_id "${test_idx} - ${NUM_TEST_FILES}")
   if(ADD_FDB_TEST_UNIT)
     message(STATUS
       "ADDING UNIT TEST ${assigned_id} ${test_name}")
diff --git a/tests/TestRunner/TestRunner.py b/tests/TestRunner/TestRunner.py
index d8e1d361a3d..1be65c25d82 100755
--- a/tests/TestRunner/TestRunner.py
+++ b/tests/TestRunner/TestRunner.py
@@ -282,12 +282,10 @@ def run_simulation_test(basedir, options):
     pargs.append(options.log_format)
     test_dir = td.get_current_test_dir()
     if options.seed is not None:
-        pargs.append('-s')
         seed = int(options.seed, 0)
         if options.test_number:
             idx = int(options.test_number)
             seed = ((seed + idx) % (2**32-2)) + 1
-        pargs.append("{}".format(seed))
     wd = os.path.join(test_dir,
                       'test_{}'.format(options.name.replace('/', '_')))
     os.mkdir(wd)
@@ -300,7 +298,12 @@ def run_simulation_test(basedir, options):
             tmp[0] = options.old_binary
         if not first:
             tmp.append('-R')
+            if seed is not None:
+                seed = ((seed + 1) % (2**32-2))
         first = False
+        if seed is not None:
+            tmp.append('-s')
+            tmp.append("{}".format(seed))
         tmp.append('-f')
         tmp.append(testfile)
         command = ' '.join(tmp)
@@ -311,23 +314,24 @@ def run_simulation_test(basedir, options):
                                 cwd=wd)
         proc.wait()
         return_codes[command] = proc.returncode
-        if proc.returncode != 0:
-            break
-    outfile = os.path.join(test_dir, 'traces.{}'.format(options.log_format))
-    res = True
-    if options.aggregate_traces == 'NONE':
-        res = process_traces(basedir, options.name,
-                             wd, None, 'NONE', options.symbolicate,
-                             options.log_format, return_codes, options.seed)
-    else:
-        with open(outfile, 'a') as f:
-            os.lockf(f.fileno(), os.F_LOCK, 0)
-            pos = f.tell()
+        outfile = os.path.join(test_dir, 'traces.{}'.format(options.log_format))
+        res = True
+        if options.aggregate_traces == 'NONE':
             res = process_traces(basedir, options.name,
-                                 wd, f, options.aggregate_traces, options.symbolicate,
+                                 wd, None, 'NONE', options.symbolicate,
                                  options.log_format, return_codes, options.seed)
-            f.seek(pos)
-            os.lockf(f.fileno(), os.F_ULOCK, 0)
+
+        else:
+            with open(outfile, 'a') as f:
+                os.lockf(f.fileno(), os.F_LOCK, 0)
+                pos = f.tell()
+                res = process_traces(basedir, options.name,
+                                     wd, f, options.aggregate_traces, options.symbolicate,
+                                     options.log_format, return_codes, options.seed)
+                f.seek(pos)
+                os.lockf(f.fileno(), os.F_ULOCK, 0)
+        if proc.returncode != 0 or res == False:
+            break
     if options.keep_logs == 'NONE' or options.keep_logs == 'FAILED' and res:
         print("Deleting old logs in {}".format(wd))
         traces = get_traces(wd, options.log_format)