diff --git a/debian/changelog b/debian/changelog
index b556377..34a4112 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -3,6 +3,10 @@ patroni (2.1.1-2) UNRELEASED; urgency=medium
   [ Christoph Berg ]
   * debian/tests/control: Give Test-Commands meaningful names.
 
+  [ Michael Banck ]
+  * debian/patches/dcs-last-seen.patch: New patch, taken from upstream commit
+    2f31e88b.
+
  -- Debian PostgreSQL Maintainers <team+postgresql@tracker.debian.org>  Fri, 20 Aug 2021 10:54:10 +0200
 
 patroni (2.1.1-1) unstable; urgency=medium
diff --git a/debian/patches/dcs-last-seen.patch b/debian/patches/dcs-last-seen.patch
new file mode 100644
index 0000000..1274740
--- /dev/null
+++ b/debian/patches/dcs-last-seen.patch
@@ -0,0 +1,154 @@
+From 2f31e88bdc3f933f0c3fffdc6ea67a99a7c378cc Mon Sep 17 00:00:00 2001
+From: Michael Banck <michael.banck@credativ.de>
+Date: Wed, 22 Sep 2021 10:01:35 +0200
+Subject: [PATCH] Add dcs_last_seen field to API (#2051)
+
+This field notes the last time (as unix epoch) a cluster member has successfully communicated with the DCS. This is useful to identify and/or analyze network partitions.
+
+Also, expose dcs_last_seen in the MemberStatus class and its from_api_response() method.
+---
+ patroni/api.py          |  6 ++++++
+ patroni/dcs/__init__.py |  7 +++++++
+ patroni/ha.py           | 12 ++++++++----
+ tests/test_api.py       |  3 ++-
+ tests/test_ha.py        |  7 ++++---
+ 5 files changed, 27 insertions(+), 8 deletions(-)
+
+diff --git a/patroni/api.py b/patroni/api.py
+index eeffaf2cf..c6adbb734 100644
+--- a/patroni/api.py
++++ b/patroni/api.py
+@@ -288,6 +288,11 @@ def do_GET_metrics(self):
+         metrics.append("# TYPE patroni_postgres_timeline counter")
+         metrics.append("patroni_postgres_timeline{0} {1}".format(scope_label, postgres.get('timeline', 0)))
+ 
++        metrics.append("# HELP patroni_dcs_last_seen Epoch timestamp when DCS was last contacted successfully"
++                       " by Patroni.")
++        metrics.append("# TYPE patroni_dcs_last_seen gauge")
++        metrics.append("patroni_dcs_last_seen{0} {1}".format(scope_label, postgres.get('dcs_last_seen', 0)))
++
+         self._write_response(200, '\n'.join(metrics)+'\n', content_type='text/plain')
+ 
+     def _read_json_content(self, body_is_optional=False):
+@@ -600,6 +605,7 @@ def get_postgresql_status(self, retry=False):
+                 'role': 'replica' if row[1] == 0 else 'master',
+                 'server_version': postgresql.server_version,
+                 'cluster_unlocked': bool(not cluster or cluster.is_unlocked()),
++                'dcs_last_seen': self.server.patroni.dcs.last_seen,
+                 'xlog': ({
+                     'received_location': row[4] or row[3],
+                     'replayed_location': row[3],
+diff --git a/patroni/dcs/__init__.py b/patroni/dcs/__init__.py
+index 38b1e27d9..d96087d16 100644
+--- a/patroni/dcs/__init__.py
++++ b/patroni/dcs/__init__.py
+@@ -652,6 +652,7 @@ def __init__(self, config):
+         self._cluster_valid_till = 0
+         self._cluster_thread_lock = Lock()
+         self._last_lsn = ''
++        self._last_seen = 0
+         self._last_status = {}
+         self.event = Event()
+ 
+@@ -722,6 +723,10 @@ def reload_config(self, config):
+     def loop_wait(self):
+         return self._loop_wait
+ 
++    @property
++    def last_seen(self):
++        return self._last_seen
++
+     @abc.abstractmethod
+     def _load_cluster(self):
+         """Internally this method should build  `Cluster` object which
+@@ -744,6 +749,8 @@ def get_cluster(self, force=False):
+             self.reset_cluster()
+             raise
+ 
++        self._last_seen = int(time.time())
++
+         with self._cluster_thread_lock:
+             self._cluster = cluster
+             self._cluster_valid_till = time.time() + self.ttl
+diff --git a/patroni/ha.py b/patroni/ha.py
+index 209a52182..83c289c51 100644
+--- a/patroni/ha.py
++++ b/patroni/ha.py
+@@ -21,13 +21,15 @@
+ logger = logging.getLogger(__name__)
+ 
+ 
+-class _MemberStatus(namedtuple('_MemberStatus', ['member', 'reachable', 'in_recovery', 'timeline',
+-                                                 'wal_position', 'tags', 'watchdog_failed'])):
++class _MemberStatus(namedtuple('_MemberStatus', ['member', 'reachable', 'in_recovery',
++                                                 'dcs_last_seen', 'timeline', 'wal_position',
++                                                 'tags', 'watchdog_failed'])):
+     """Node status distilled from API response:
+ 
+         member - dcs.Member object of the node
+         reachable - `!False` if the node is not reachable or is not responding with correct JSON
+         in_recovery - `!True` if pg_is_in_recovery() == true
++        dcs_last_seen - timestamp from JSON of last succesful communication with DCS
+         timeline - timeline value from JSON
+         wal_position - maximum value of `replayed_location` or `received_location` from JSON
+         tags - dictionary with values of different tags (i.e. nofailover)
+@@ -37,12 +39,14 @@ class _MemberStatus(namedtuple('_MemberStatus', ['member', 'reachable', 'in_reco
+     def from_api_response(cls, member, json):
+         is_master = json['role'] == 'master'
+         timeline = json.get('timeline', 0)
++        dcs_last_seen = json.get('dcs_last_seen', 0)
+         wal = not is_master and max(json['xlog'].get('received_location', 0), json['xlog'].get('replayed_location', 0))
+-        return cls(member, True, not is_master, timeline, wal, json.get('tags', {}), json.get('watchdog_failed', False))
++        return cls(member, True, not is_master, dcs_last_seen, timeline, wal,
++                   json.get('tags', {}), json.get('watchdog_failed', False))
+ 
+     @classmethod
+     def unknown(cls, member):
+-        return cls(member, False, None, 0, 0, {}, False)
++        return cls(member, False, None, 0, 0, 0, {}, False)
+ 
+     def failover_limitation(self):
+         """Returns reason why this node can't promote or None if everything is ok."""
+diff --git a/tests/test_api.py b/tests/test_api.py
+index 34a6224eb..60c3dd038 100644
+--- a/tests/test_api.py
++++ b/tests/test_api.py
+@@ -54,6 +54,7 @@ class MockHa(object):
+ 
+     state_handler = MockPostgresql()
+     watchdog = MockWatchdog()
++    dcs_last_seen = 0
+ 
+     @staticmethod
+     def is_leader():
+@@ -77,7 +78,7 @@ def delete_future_restart():
+ 
+     @staticmethod
+     def fetch_nodes_statuses(members):
+-        return [_MemberStatus(None, True, None, 0, None, {}, False)]
++        return [_MemberStatus(None, True, None, 0, 0, None, {}, False)]
+ 
+     @staticmethod
+     def schedule_future_restart(data):
+diff --git a/tests/test_ha.py b/tests/test_ha.py
+index 3228be697..0f30a1102 100644
+--- a/tests/test_ha.py
++++ b/tests/test_ha.py
+@@ -80,13 +80,14 @@ def get_standby_cluster_initialized_with_only_leader(failover=None, sync=None):
+     )
+ 
+ 
+-def get_node_status(reachable=True, in_recovery=True, timeline=2,
+-                    wal_position=10, nofailover=False, watchdog_failed=False):
++def get_node_status(reachable=True, in_recovery=True, dcs_last_seen=0,
++                    timeline=2, wal_position=10, nofailover=False,
++                    watchdog_failed=False):
+     def fetch_node_status(e):
+         tags = {}
+         if nofailover:
+             tags['nofailover'] = True
+-        return _MemberStatus(e, reachable, in_recovery, timeline, wal_position, tags, watchdog_failed)
++        return _MemberStatus(e, reachable, in_recovery, dcs_last_seen, timeline, wal_position, tags, watchdog_failed)
+     return fetch_node_status
+ 
+ 
diff --git a/debian/patches/series b/debian/patches/series
index 29713ae..bbd6fd4 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -5,3 +5,4 @@ offline_intersphinx.patch
 regression_tests_disable_requirement_download.patch
 requirements_cdiff.patch
 regression_tests_disable_raft_tests.py
+dcs-last-seen.patch