diff --git a/teuthology/describe_tests.py b/teuthology/describe_tests.py
index 3ea7d71b6..c0054adc1 100644
--- a/teuthology/describe_tests.py
+++ b/teuthology/describe_tests.py
@@ -137,7 +137,8 @@ def output_summary(path, limit=0,
                                  filter_in=filter_in,
                                  filter_out=filter_out,
                                  filter_all=filter_all,
-                                 filter_fragments=filter_fragments)
+                                 filter_fragments=filter_fragments,
+                                 seed=seed)
     for c in configs:
         if limit and count >= limit:
             break
@@ -185,7 +186,8 @@ def get_combinations(suite_dir,
                                  filter_in=filter_in,
                                  filter_out=filter_out,
                                  filter_all=filter_all,
-                                 filter_fragments=filter_fragments)
+                                 filter_fragments=filter_fragments,
+                                 seed=seed)
     for _, fragment_paths, __ in configs:
         if limit > 0 and num_listed >= limit:
             break
diff --git a/teuthology/suite/merge.py b/teuthology/suite/merge.py
index 647fe6e1d..1f8271fdc 100644
--- a/teuthology/suite/merge.py
+++ b/teuthology/suite/merge.py
@@ -115,6 +115,9 @@ def config_merge(configs, suite_name=None, **kwargs):
     the entire job (config) from the list.
     """
 
+    seed = kwargs.get('seed', 1)
+    log.debug("configuring Lua randomseed to %d", seed)
+    L.eval(f'local math = require"math"; math.randomseed({seed});')
     new_script = L.eval('new_script')
     yaml_cache = {}
     for desc, paths in configs:
diff --git a/teuthology/suite/run.py b/teuthology/suite/run.py
index b69b80b58..bea31432f 100644
--- a/teuthology/suite/run.py
+++ b/teuthology/suite/run.py
@@ -591,6 +591,7 @@ def schedule_suite(self):
             filter_out=self.args.filter_out,
             filter_all=self.args.filter_all,
             filter_fragments=self.args.filter_fragments,
+            seed=self.args.seed,
             suite_name=suite_name))
 
         if self.args.dry_run: