diff --git a/packaging/common/cfengine-hub/postinstall.sh b/packaging/common/cfengine-hub/postinstall.sh
index 1cfa329aa..c18493aaf 100644
--- a/packaging/common/cfengine-hub/postinstall.sh
+++ b/packaging/common/cfengine-hub/postinstall.sh
@@ -429,37 +429,40 @@ init_postgres_dir()
     if [ -f "$BACKUP_DIR/data/postgresql.conf.modified" ]; then
       # User-modified file from the previous old version of CFEngine exists, try to use it.
       cp -a "$BACKUP_DIR/data/postgresql.conf.modified" "$PREFIX/state/pg/data/postgresql.conf"
-      # start subshell to disable error handling temporarily
-      (
-        set +e
-        (cd /tmp && su cfpostgres -c "$PREFIX/bin/pg_ctl -w -D $PREFIX/state/pg/data -l /var/log/postgresql.log start")
-        if [ $? = 0 ]; then
-          # Started successfully, stop it again, the migration requires it to be not running.
-          (cd /tmp && su cfpostgres -c "$PREFIX/bin/pg_ctl -w -D $PREFIX/state/pg/data -l /var/log/postgresql.log stop")
-
-          # Wait a while if we have to for the server to be stopped
-          if ! wait_for_cf_postgres_down; then
-            cf_console echo "Error: unable to shutdown postgresql server. Showing last of /var/log/postgresql.log for clues."
-            cf_console tail /var/log/postgresql.log
-            exit 1
-          fi
-          # Copy over the new config as well, user should take at look at it.
-          cf_console echo "Installing the $pgconfig_type postgresql.conf file as $PREFIX/state/pg/data/postgresql.conf.new."
-          cf_console echo "Please review it and update $PREFIX/state/pg/data/postgresql.conf accordingly."
-          cp -a "$new_pgconfig_file" "$PREFIX/state/pg/data/postgresql.conf.new"
-          chown cfpostgres "$PREFIX/state/pg/data/postgresql.conf.new"
-        else
-          # Failed to start, move the old file aside and use the new one.
-          mv "$PREFIX/state/pg/data/postgresql.conf" "$PREFIX/state/pg/data/postgresql.conf.old"
-          cf_console echo "Warning: failed to use the old postgresql.conf file, using the $pgconfig_type one."
-          cf_console echo "Please review the $PREFIX/state/pg/data/postgresql.conf file and update it accordingly."
-          cf_console echo "The original file was saved as $PREFIX/state/pg/data/postgresql.conf.old"
-          cf_console echo "last 10 lines of /var/log/postgresql.log for determining cause of failure"
-          cf_console tail -10 /var/log/postgresql.log
-          cp -a "$new_pgconfig_file" "$PREFIX/state/pg/data/postgresql.conf"
-          chown cfpostgres "$PREFIX/state/pg/data/postgresql.conf"
+      failure=0
+      (cd /tmp && su cfpostgres -c "$PREFIX/bin/pg_ctl -w -D $PREFIX/state/pg/data -l /var/log/postgresql.log start") || failure=1
+      if [ $failure = 0 ]; then
+        wait_for_cf_postgres || failure=1
+      fi
+      if [ $failure = 0 ]; then
+        # Started successfully, stop it again, the migration requires it to be not running.
+        (cd /tmp && su cfpostgres -c "$PREFIX/bin/pg_ctl -w -D $PREFIX/state/pg/data -l /var/log/postgresql.log stop") || failure=1
+        if [ $failure = 0 ]; then
+          wait_for_cfpostgres_down || failure=1
+        fi
+        if [ $failure != 0 ]; then
+          cf_console echo "Error: unable to shutdown postgresql server. Showing last of /var/log/postgresql.log for clues."
+          cf_console tail /var/log/postgresql.log
+          # this is a fatal error and so we exit instead of return
+          # steps after this init_postgres_dir() function should not continue if we can't start/stop the server
+          exit 1
         fi
-      )
+        # Copy over the new config as well, user should take at look at it.
+        cf_console echo "Installing the $pgconfig_type postgresql.conf file as $PREFIX/state/pg/data/postgresql.conf.new."
+        cf_console echo "Please review it and update $PREFIX/state/pg/data/postgresql.conf accordingly."
+        cp -a "$new_pgconfig_file" "$PREFIX/state/pg/data/postgresql.conf.new"
+        chown cfpostgres "$PREFIX/state/pg/data/postgresql.conf.new"
+      else
+        # Failed to start, move the old file aside and use the new one.
+        mv "$PREFIX/state/pg/data/postgresql.conf" "$PREFIX/state/pg/data/postgresql.conf.old"
+        cf_console echo "Warning: failed to use the old postgresql.conf file, using the $pgconfig_type one."
+        cf_console echo "Please review the $PREFIX/state/pg/data/postgresql.conf file and update it accordingly."
+        cf_console echo "The original file was saved as $PREFIX/state/pg/data/postgresql.conf.old"
+        cf_console echo "last 10 lines of /var/log/postgresql.log for determining cause of failure"
+        cf_console tail /var/log/postgresql.log
+        cp -a "$new_pgconfig_file" "$PREFIX/state/pg/data/postgresql.conf"
+        chown cfpostgres "$PREFIX/state/pg/data/postgresql.conf"
+      fi
     else
       # No user-modified file, just use the new recommended or default config (see generate_new_postgres_conf())
       cp -a "$new_pgconfig_file" "$PREFIX/state/pg/data/postgresql.conf"