diff --git a/doc/man-sections/advanced-options.rst b/doc/man-sections/advanced-options.rst
index e1115e4..73ca44a 100644
--- a/doc/man-sections/advanced-options.rst
+++ b/doc/man-sections/advanced-options.rst
@@ -36,7 +36,8 @@
 
      hash-size r v
 
-  By default, both tables are sized at 256 buckets.
+  By default, both tables are sized at 4 times ``--max-clients`` buckets.
+  With the default of 1024 of ``--max-clients`` this gives 4096 buckets.
 
 --bcast-buffers n
   Allocate ``n`` buffers for broadcast datagrams (default :code:`256`).
diff --git a/doc/man-sections/server-options.rst b/doc/man-sections/server-options.rst
index 03ce651..eb8e273 100644
--- a/doc/man-sections/server-options.rst
+++ b/doc/man-sections/server-options.rst
@@ -414,7 +414,7 @@
      iroute-ipv6 ipv6addr/bits
 
 --max-clients n
-  Limit server to a maximum of ``n`` concurrent clients.
+  Limit server to a maximum of ``n`` concurrent clients. Defaults to 1024.
 
 --max-routes-per-client n
   Allow a maximum of ``n`` internal routes per client (default
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 1db781d..24f2407 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -849,8 +849,6 @@
 #endif
     o->vlan_accept = VLAN_ALL;
     o->vlan_pvid = 1;
-    o->real_hash_size = 256;
-    o->virtual_hash_size = 256;
     o->n_bcast_buf = 256;
     o->tcp_queue_limit = 64;
     o->max_clients = 1024;
@@ -3724,6 +3722,22 @@
     gc_free(&gc);
 }
 #endif /* if defined(_WIN32) || defined(TARGET_ANDROID) */
+/**
+ * Sets the internal hash maps sizes according to the max_clients
+ *
+ */
+static void
+helper_hashmap_sizes(struct options *o)
+{
+    if (!o->real_hash_size)
+    {
+        o->real_hash_size = 4 * o->max_clients;
+    }
+    if (!o->virtual_hash_size)
+    {
+        o->virtual_hash_size = 4 * o->max_clients;
+    }
+}
 
 static void
 options_postprocess_mutate(struct options *o, struct env_set *es)
@@ -3739,6 +3753,11 @@
     helper_keepalive(o);
     helper_tcp_nodelay(o);
 
+    if (o->mode == MODE_SERVER)
+    {
+        helper_hashmap_sizes(o);
+    }
+
     options_postprocess_setdefault_ncpciphers(o);
     options_set_backwards_compatible_options(o);
     options_process_mutate_prf(o);