diff -Nru corosync-2.3.5/debian/changelog corosync-2.3.5/debian/changelog
--- corosync-2.3.5/debian/changelog	2017-12-20 11:37:52.000000000 +0000
+++ corosync-2.3.5/debian/changelog	2018-02-26 15:50:16.000000000 +0000
@@ -1,3 +1,14 @@
+corosync (2.3.5-3ubuntu2.1) xenial; urgency=high
+
+  * Properly restart corosync and pacemaker together (LP: #1740892)
+    - d/rules: pass --restart-after-upgrade to dh_installinit
+    - d/control: indicate this version breaks all older pacemaker, to
+      force an upgrade of pacemaker.
+    - d/corosync.postinst: if flagged to do so by pacemaker, start
+      pacemaker on upgrade.
+
+ -- Eric Desrochers <eric.desrochers@canonical.com>  Mon, 19 Feb 2018 09:28:34 -0500
+
 corosync (2.3.5-3ubuntu2) xenial; urgency=medium
 
   * d/p/Parser-Make-config-file-parser-more-hierarchy.patch: Fixes how
diff -Nru corosync-2.3.5/debian/control corosync-2.3.5/debian/control
--- corosync-2.3.5/debian/control	2016-04-01 13:52:10.000000000 +0000
+++ corosync-2.3.5/debian/control	2018-02-26 15:50:16.000000000 +0000
@@ -38,6 +38,7 @@
  lsb-base (>= 3.0-6),
  adduser,
  xsltproc
+Breaks: pacemaker (<< 1.1.14-2ubuntu1.4)
 Description: cluster engine daemon and utilities
  ${DESCRIPTION}
  This package contains the Corosync daemon and some administration tools.
diff -Nru corosync-2.3.5/debian/corosync.postinst corosync-2.3.5/debian/corosync.postinst
--- corosync-2.3.5/debian/corosync.postinst	2015-09-23 14:58:18.000000000 +0000
+++ corosync-2.3.5/debian/corosync.postinst	2018-02-26 15:50:16.000000000 +0000
@@ -6,6 +6,16 @@
 	echo 'This file is here to keep the log dir around after package removal
 until #588515 is fixed.' >/var/log/corosync/.empty
 	# really was empty before 2.3.5-1
+
+	# For upgrades from older corosync, look for a flag from
+	# pacemaker that it was running before upgrade. See LP: #1740892
+	if dpkg --compare-versions "$2" lt "2.3.5-3ubuntu2.1"; then
+		if [ -f /run/pacemaker-was-running-lp1740892-workaround ]; then
+			if deb-systemd-invoke start pacemaker >/dev/null 2>&1; then
+				rm -f /run/pacemaker-was-running-lp1740892-workaround
+			fi
+		fi
+	fi
 fi
 
 #DEBHELPER#
diff -Nru corosync-2.3.5/debian/rules corosync-2.3.5/debian/rules
--- corosync-2.3.5/debian/rules	2015-10-22 13:36:41.000000000 +0000
+++ corosync-2.3.5/debian/rules	2018-02-26 15:50:16.000000000 +0000
@@ -54,6 +54,9 @@
 override_dh_installchangelogs:
 	dh_installchangelogs ChangeLog
 
+override_dh_installinit:
+	dh_installinit --restart-after-upgrade
+
 override_dh_strip:
 	dh_strip --dbg-package=corosync-dbg