diff --git a/src/debug.cpp b/src/debug.cpp
index c51ff0673..4977f59df 100644
--- a/src/debug.cpp
+++ b/src/debug.cpp
@@ -829,6 +829,13 @@ NULL
             c->flags &= ~(CLIENT_MASTER | CLIENT_MASTER_FORCE_REPLY);
         }
         addReply(c, shared.ok);
+    } else if (!strcasecmp(szFromObj(c->argv[1]),"truncate-repl-backlog") && c->argc == 2) {
+        g_pserver->repl_backlog_idx = 0;
+        g_pserver->repl_backlog_off = g_pserver->master_repl_offset+1;
+        g_pserver->repl_backlog_histlen = 0;
+        if (g_pserver->repl_batch_idxStart >= 0) g_pserver->repl_batch_idxStart = -1;
+        if (g_pserver->repl_batch_offStart >= 0) g_pserver->repl_batch_offStart = -1;
+        addReply(c, shared.ok);
     } else if (!strcasecmp(szFromObj(c->argv[1]),"config-rewrite-force-all") && c->argc == 2)
     {
         if (rewriteConfig(cserver.configfile, 1) == -1)
diff --git a/tests/unit/moduleapi/testrdb.tcl b/tests/unit/moduleapi/testrdb.tcl
index 2298a73c5..9b5d8fdaf 100644
--- a/tests/unit/moduleapi/testrdb.tcl
+++ b/tests/unit/moduleapi/testrdb.tcl
@@ -96,7 +96,7 @@ tags "modules" {
                             $master client kill type replica
                             $master set asdf asdf
                             # the side effect of resizing the backlog is that it is flushed (16k is the min size)
-                            $master config set repl-backlog-size [expr {16384 + $i}]
+                            $master debug truncate-repl-backlog
                             $master exec
                         }
                         # wait for loading to stop (fail)