diff --git a/qa/cephfs/conf/mon.yaml b/qa/cephfs/conf/mon.yaml
index eea56004a40b6..e32f0fd354732 100644
--- a/qa/cephfs/conf/mon.yaml
+++ b/qa/cephfs/conf/mon.yaml
@@ -3,3 +3,5 @@ overrides:
     conf:
       mon:
         mon op complaint time: 120
+        # cephadm can take up to 5 minutes to bring up remaining mons
+        mon down mkfs grace: 300
diff --git a/qa/cephfs/overrides/ignorelist_wrongly_marked_down.yaml b/qa/cephfs/overrides/ignorelist_wrongly_marked_down.yaml
index c9c46cc48f413..41ba84f04db5e 100644
--- a/qa/cephfs/overrides/ignorelist_wrongly_marked_down.yaml
+++ b/qa/cephfs/overrides/ignorelist_wrongly_marked_down.yaml
@@ -7,4 +7,3 @@ overrides:
       - but it is still running
 # MDS daemon 'b' is not responding, replacing it as rank 0 with standby 'a'
       - is not responding
-      - MON_DOWN
diff --git a/qa/tasks/mgr/dashboard/test_health.py b/qa/tasks/mgr/dashboard/test_health.py
index 3ebea97e3d29e..5b181968633c1 100644
--- a/qa/tasks/mgr/dashboard/test_health.py
+++ b/qa/tasks/mgr/dashboard/test_health.py
@@ -268,7 +268,8 @@ def test_full_health(self):
                 'state': str,
                 # @TODO: What type should be expected here?
                 'sync_provider': JList(JAny(none=True)),
-                'stretch_mode': bool
+                'stretch_mode': bool,
+                'uptime': int,
             }),
             'osd_map': JObj({
                 # @TODO: define schema for crush map and osd_metadata, among
diff --git a/src/common/options/mon.yaml.in b/src/common/options/mon.yaml.in
index ff8813c982f94..379917445c0f0 100644
--- a/src/common/options/mon.yaml.in
+++ b/src/common/options/mon.yaml.in
@@ -55,6 +55,15 @@ options:
   default: 1_min
   services:
   - mon
+- name: mon_down_uptime_grace
+  type: secs
+  level: advanced
+  desc: Period in seconds that the cluster may have a mon down after this (leader) monitor comes up.
+  default: 1_min
+  services:
+  - mon
+  flags:
+  - runtime
 - name: mon_mgr_beacon_grace
   type: secs
   level: advanced
diff --git a/src/mon/HealthMonitor.cc b/src/mon/HealthMonitor.cc
index 4d2303d09fbcf..45563f87d3d04 100644
--- a/src/mon/HealthMonitor.cc
+++ b/src/mon/HealthMonitor.cc
@@ -803,9 +803,14 @@ void HealthMonitor::check_for_mon_down(health_check_map_t *checks)
 {
   int max = mon.monmap->size();
   int actual = mon.get_quorum().size();
-  const auto now = ceph::real_clock::now();
+  const auto rcnow = ceph::real_clock::now();
+  const auto created = mon.monmap->created.to_real_time();
+  const auto mcnow = ceph::coarse_mono_clock::now();
+  const auto starttime = mon.get_starttime();
+
   if (actual < max &&
-      now > mon.monmap->created.to_real_time() + g_conf().get_val<std::chrono::seconds>("mon_down_mkfs_grace")) {
+      (rcnow - created) > g_conf().get_val<std::chrono::seconds>("mon_down_mkfs_grace") &&
+      (mcnow - starttime) > g_conf().get_val<std::chrono::seconds>("mon_down_uptime_grace")) {
     ostringstream ss;
     ss << (max-actual) << "/" << max << " mons down, quorum "
        << mon.get_quorum_names();
diff --git a/src/mon/Monitor.cc b/src/mon/Monitor.cc
index a0fe3fa038e60..a70bfbe33c9de 100644
--- a/src/mon/Monitor.cc
+++ b/src/mon/Monitor.cc
@@ -2672,6 +2672,7 @@ void Monitor::get_mon_status(Formatter *f)
   f->dump_int("rank", rank);
   f->dump_string("state", get_state_name());
   f->dump_int("election_epoch", get_epoch());
+  f->dump_int("uptime", get_uptime().count());
 
   f->open_array_section("quorum");
   for (set<int>::iterator p = quorum.begin(); p != quorum.end(); ++p) {
diff --git a/src/mon/Monitor.h b/src/mon/Monitor.h
index ed1e2a4e8a95d..13afacafde7dd 100644
--- a/src/mon/Monitor.h
+++ b/src/mon/Monitor.h
@@ -1099,6 +1099,18 @@ class Monitor : public Dispatcher,
   }
 
   bool is_keyring_required();
+
+public:
+  ceph::coarse_mono_time get_starttime() const {
+    return starttime;
+  }
+  std::chrono::milliseconds get_uptime() const {
+    auto now = ceph::coarse_mono_clock::now();
+    return std::chrono::duration_cast<std::chrono::milliseconds>(now-starttime);
+  }
+
+private:
+  ceph::coarse_mono_time const starttime = coarse_mono_clock::now();
 };
 
 #define CEPH_MON_FEATURE_INCOMPAT_BASE CompatSet::Feature (1, "initial feature set (~v.18)")