From: bodea <bodea>
Date: Sun, 22 May 2005 04:15:32 +0000 (+0000)
Subject: Any ping from what we think is the master should force an election.
X-Git-Tag: release_2_0_21~3
X-Git-Url: http://git.sameswireless.fr/l2tpns.git/commitdiff_plain/7b9fe631a04e8a92b0c8f949709dc1a88a1063bc

Any ping from what we think is the master should force an election.
---

diff --git a/Changes b/Changes
index 12cb3f8..56cf0e9 100644
--- a/Changes
+++ b/Changes
@@ -1,4 +1,4 @@
-* Sat May 21 2005 Brendan O'Dea <bod@optusnet.com.au> 2.0.21
+* Sun May 22 2005 Brendan O'Dea <bod@optusnet.com.au> 2.0.21
 - Cluster changes from Michael, intended to prevent a stray master
   from trashing a cluster:
   + Ignore heartbeats from peers claiming to be the master before the
@@ -8,9 +8,10 @@
   + Keep probing the master for late heartbeats.
   + Drop BGP as soon as we become master with peers (TODO: pre-emptively
     drop routes if the master is late and we are the best candidate).
-  + A slave (presumably a recently restarted master) receiving a
-    LASTSEEN message sends a zero basetime ping (as sent by the master
-    on clean shutdown).
+  + Any PING seen from a master forces an election (rather than just
+    where basetime is zero).
+  + A slave which receives a LASTSEEN message (presumably a restarted
+    master) sends back a ping, indicating that it's not the master.
   
 * Mon May 16 2005 Brendan O'Dea <bod@optusnet.com.au> 2.0.20
 - Add handling of "throttle=N" RADIUS attributes.
diff --git a/cluster.c b/cluster.c
index 6f72394..554b4a8 100644
--- a/cluster.c
+++ b/cluster.c
@@ -1,6 +1,6 @@
 // L2TPNS Clustering Stuff
 
-char const *cvs_id_cluster = "$Id: cluster.c,v 1.26.2.6 2005/05/21 13:05:36 bodea Exp $";
+char const *cvs_id_cluster = "$Id: cluster.c,v 1.26.2.7 2005/05/22 04:15:32 bodea Exp $";
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -354,9 +354,9 @@ static void send_heartbeat(int seq, char *data, int size)
 }
 
 //
-// Send an 'i am alive' message to every machine in the cluster.
+// Send an 'i am alive' message to every machine in the cluster, or to a single peer
 //
-void cluster_send_ping(time_t basetime)
+static void send_ping(time_t basetime, in_addr_t peer)
 {
 	char buff[100 + sizeof(pingt)];
 	char *p = buff;
@@ -365,15 +365,29 @@ void cluster_send_ping(time_t basetime)
 	if (config->cluster_iam_master && basetime)		// We're heartbeating so no need to ping.
 		return;
 
-	LOG(5, 0, 0, "Sending cluster ping...\n");
-
 	x.ver = 1;
 	x.addr = config->bind_address;
 	x.undef = config->cluster_undefined_sessions + config->cluster_undefined_tunnels;
 	x.basetime = basetime;
 
 	add_type(&p, C_PING, basetime, (char *) &x, sizeof(x));
-	cluster_send_data(buff, (p-buff) );
+
+	if (peer)
+		peer_send_data(peer, buff, (p-buff));
+	else
+		cluster_send_data(buff, (p-buff) );
+}
+
+void cluster_send_ping(time_t basetime)
+{
+	LOG(5, 0, 0, "Sending cluster ping...\n");
+	send_ping(0, basetime);
+}
+
+void peer_send_ping(in_addr_t peer, time_t basetime)
+{
+	LOG(5, 0, 0, "Sending unicast ping to %s...\n", fmtaddr(peer, 0));
+	send_ping(peer, basetime);
 }
 
 //
@@ -903,11 +917,9 @@ static int cluster_catchup_slave(int seq, in_addr_t slave)
 
 	LOG(1, 0, 0, "Slave %s sent LASTSEEN with seq %d\n", fmtaddr(slave, 0), seq);
 	if (!config->cluster_iam_master) {
-		LOG(1, 0, 0, "Got LASTSEEN but I'm not a master! Sending a null PING.\n");
-			// Send a ping to the stray slave saying that we're a master that's
-			// just shutdown. This should force the slave to listen for the real
-			// master.
-		peer_send_message(slave, C_PING, 0, NULL, 0);
+		LOG(1, 0, 0, "Got LASTSEEN but I'm not a master! Sending a PING.\n");
+			// Send a ping to the slave so they know we're no longer a master
+		peer_send_ping(slave, basetime);
 		return 0;
 	}
 
@@ -978,8 +990,10 @@ static int cluster_add_peer(in_addr_t peer, time_t basetime, pingt *pp, int size
 	}
 
 	// Is this the master shutting down??
-	if (peer == config->cluster_master_address && !basetime) {
-		LOG(3, 0, 0, "Master %s shutting down...\n", fmtaddr(config->cluster_master_address, 0));
+	if (peer == config->cluster_master_address) {
+		LOG(3, 0, 0, "Master %s %s\n", fmtaddr(config->cluster_master_address, 0),
+			basetime ? "has restarted!" : "shutting down...");
+
 		config->cluster_master_address = 0;
 		config->cluster_last_hb = 0; // Force an election.
 		cluster_check_master();
diff --git a/l2tpns.spec b/l2tpns.spec
index c05c025..3280818 100644
--- a/l2tpns.spec
+++ b/l2tpns.spec
@@ -43,5 +43,5 @@ rm -rf %{buildroot}
 %attr(644,root,root) /usr/share/man/man[58]/*
 
 %changelog
-* Sat May 21 2005 Brendan O'Dea <bod@optusnet.com.au> 2.0.21-1
+* Sun May 22 2005 Brendan O'Dea <bod@optusnet.com.au> 2.0.21-1
 - 2.0.21 release, see /usr/share/doc/l2tpns-2.0.21/Changes