[Cluster-devel] [PATCH 2/2] rgmanager: Avoid duplicate restart of service (RHEL5)

[Lon Hohberger]

If B depends on A and both A and B are running on
node 1 and node 1 fails, the stop events generated
will inadvertently cause B to be restarted after
the initial failover.

This patch resolves this issue by comparing the
start times in central_processing mode.

A known limitation to this patch is that in order
for this patch to work correctly, the cluster nodes'
time must be approximately in sync.

Resolves: rhbz#743214

Signed-off-by: Lon Hohberger <lhh at redhat.com>
---
 rgmanager/src/resources/default_event_script.sl |   19 ++++++++++++++++++-
 1 files changed, 18 insertions(+), 1 deletions(-)

diff --git a/rgmanager/src/resources/default_event_script.sl b/rgmanager/src/resources/default_event_script.sl
index cdde066..2d5503f 100644
--- a/rgmanager/src/resources/default_event_script.sl
+++ b/rgmanager/src/resources/default_event_script.sl
@@ -444,6 +444,8 @@ define default_service_event_handler()
 	variable tmp;
 	variable owner;
 	variable state;
+	variable d_trans, s_trans;
+	variable s_state;
 
 	debug("Executing default service event handler");
 
@@ -498,17 +500,32 @@ define default_service_event_handler()
 			continue;
 		}
 
-		(,,, owner, state) = service_status(services[x]);
+		(d_trans,,,, owner, state) = service_status(services[x], 1);
 		if ((service_state == "started") and (owner < 0) and
 		    (state == "stopped")) {
 			info("Dependency met; starting ", services[x]);
 			nodes = allowed_nodes(services[x]);
 			()=move_or_start(services[x], nodes);
+			continue;
 		}
 
 		% service died - stop service(s) that depend on the dead
 		if ((service_owner < 0) and (owner >= 0) and
 		    (depend_mode != "soft")) {
+
+			% grab the -current- state of the service here
+			% If the service is running, and its dependent service
+			% as above is running and the dependent service was
+			% started at or after the service, then stopping it
+			% will result in unwanted service outage.
+			(s_trans,,,, s_state) = service_status(service_name);
+			if ((s_state == "started") and (state == "started") and
+			    (d_trans >= s_trans)) {
+				debug("Skipping ", services[x],
+				      "; restart not needed");
+				continue;
+			}
+
 			info("Dependency lost; stopping ", services[x]);
 			()=service_stop(services[x]);
 		}
-- 
1.7.3.4