X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/1389d7b677b93bf774f2e1c9e362fd43b4727e44..0bf11bc7fd93e0deafa8b6e09f89be30bf5fb824:/cluster.c

diff --git a/cluster.c b/cluster.c
index 29322fc..645403c 100644
--- a/cluster.c
+++ b/cluster.c
@@ -1,6 +1,6 @@
 // L2TPNS Clustering Stuff
 
-char const *cvs_id_cluster = "$Id: cluster.c,v 1.26.2.8 2005/05/22 12:02:41 bodea Exp $";
+char const *cvs_id_cluster = "$Id: cluster.c,v 1.26.2.11 2005/05/30 02:55:40 bodea Exp $";
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -192,7 +192,7 @@ static void add_type(char **p, int type, int more, char *data, int size)
 }
 
 // advertise our presence via BGP or gratuitous ARP
-static void advertise(void)
+static void advertise_routes(void)
 {
 #ifdef BGP
 	if (bgp_configured)
@@ -203,6 +203,15 @@ static void advertise(void)
 			send_garp(config->bind_address);	// Start taking traffic.
 }
 
+// withdraw our routes (BGP only)
+static void withdraw_routes(void)
+{
+#ifdef BGP
+	if (bgp_configured)
+		bgp_enable_routing(0);
+#endif /* BGP */
+}
+
 static void cluster_uptodate(void)
 {
 	if (config->cluster_iam_uptodate)
@@ -214,7 +223,7 @@ static void cluster_uptodate(void)
 	config->cluster_iam_uptodate = 1;
 
 	LOG(0, 0, 0, "Now uptodate with master.\n");
-	advertise();
+	advertise_routes();
 }
 
 //
@@ -354,9 +363,9 @@ static void send_heartbeat(int seq, char *data, int size)
 }
 
 //
-// Send an 'i am alive' message to every machine in the cluster, or to a single peer
+// Send an 'i am alive' message to every machine in the cluster.
 //
-static void send_ping(time_t basetime, in_addr_t peer)
+void cluster_send_ping(time_t basetime)
 {
 	char buff[100 + sizeof(pingt)];
 	char *p = buff;
@@ -365,29 +374,15 @@ static void send_ping(time_t basetime, in_addr_t peer)
 	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));
-
-	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);
-}
-
-static 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);
+	cluster_send_data(buff, (p-buff) );
 }
 
 //
@@ -470,17 +465,22 @@ void cluster_check_slaves(void)
 			continue;	// Shutdown peer! Skip them.
 
 		if (peers[i].uptodate)
-			have_peers = 1;
-
-		if (!peers[i].uptodate)
+			have_peers++;
+		else
 			config->cluster_iam_uptodate = 0; // Start fast heartbeats
 	}
 
-#ifdef BGP
-	// in a cluster, withdraw/add routes when we get a peer/lose all peers
-	if (bgp_configured && have_peers != had_peers)
-		bgp_enable_routing(!have_peers);
-#endif /* BGP */
+	// in a cluster, withdraw/add routes when we get a peer/lose peers
+	if (have_peers != had_peers)
+	{
+		if (had_peers < config->cluster_master_min_adv &&
+		    have_peers >= config->cluster_master_min_adv)
+			withdraw_routes();
+
+		else if (had_peers >= config->cluster_master_min_adv &&
+		    have_peers < config->cluster_master_min_adv)
+			advertise_routes();
+	}
 }
 
 //
@@ -493,6 +493,7 @@ void cluster_check_master(void)
 	int last_free = 0;
 	clockt t = TIME;
 	static int probed = 0;
+	int have_peers;
 
 	if (config->cluster_iam_master)
 		return;		// Only runs on the slaves...
@@ -525,7 +526,11 @@ void cluster_check_master(void)
 
 	LOG(0, 0, 0, "Master timed out! Holding election...\n");
 
-	for (i = 0; i < num_peers; i++)
+	// In the process of shutting down, can't be master
+	if (main_quit)
+		return;
+
+	for (i = have_peers = 0; i < num_peers; i++)
 	{
 		if ((peers[i].timestamp + config->cluster_hb_timeout) < t)
 			continue;	// Stale peer! Skip them.
@@ -543,6 +548,9 @@ void cluster_check_master(void)
 			LOG(1, 0, 0, "Expecting %s to become master\n", fmtaddr(peers[i].peer, 0));
 			return;		// They'll win the election. Wait for them to come up.
 		}
+
+		if (peers[i].uptodate)
+			have_peers++;
 	}
 
 		// Wow. it's been ages since I last heard a heartbeat
@@ -554,6 +562,11 @@ void cluster_check_master(void)
 
 	LOG(0, 0, 0, "I am declaring myself the master!\n");
 
+	if (have_peers < config->cluster_master_min_adv)
+		advertise_routes();
+	else
+		withdraw_routes();
+
 	if (config->cluster_seq_number == -1)
 		config->cluster_seq_number = 0;
 
@@ -634,14 +647,6 @@ void cluster_check_master(void)
 	config->cluster_undefined_tunnels = 0;
 	config->cluster_iam_uptodate = 1; // assume all peers are up-to-date
 
-	if (!num_peers) // lone master
-		advertise();
-#ifdef BGP
-	else if (bgp_configured)
-		bgp_enable_routing(0);
-#endif /* BGP */
-
-
 	// FIXME. We need to fix up the tunnel control message
 	// queue here! There's a number of other variables we
 	// should also update.
@@ -917,9 +922,10 @@ 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 PING.\n");
-			// Send a ping to the slave so they know we're no longer a master
-		peer_send_ping(slave, basetime);
+		LOG(1, 0, 0, "Got LASTSEEN but I'm not a master! Redirecting it to %s.\n",
+			fmtaddr(config->cluster_master_address, 0));
+
+		peer_send_message(slave, C_MASTER, config->cluster_master_address, NULL, 0);
 		return 0;
 	}
 
@@ -1034,6 +1040,20 @@ static int cluster_add_peer(in_addr_t peer, time_t basetime, pingt *pp, int size
 	return 1;
 }
 
+// A slave responds with C_MASTER when it gets a message which should have gone to a master.
+static int cluster_set_master(in_addr_t peer, in_addr_t master)
+{
+	if (config->cluster_iam_master)	// Sanity...
+		return 0;
+
+	LOG(3, 0, 0, "Peer %s set the master to %s...\n", fmtaddr(peer, 0),
+		fmtaddr(master, 1));
+
+	config->cluster_master_address = master;
+	cluster_check_master();
+	return 0;
+}
+
 /* Handle the slave updating the byte counters for the master. */
 //
 // Note that we don't mark the session as dirty; We rely on
@@ -1408,10 +1428,13 @@ int processcluster(char *data, int size, in_addr_t addr)
 	s -= sizeof(uint32_t);
 
 	switch (type) {
-	case C_PING:	// Update the peers table.
+	case C_PING: // Update the peers table.
 		return cluster_add_peer(addr, more, (pingt *) p, s);
 
-	case C_LASTSEEN:	// Catch up a slave (slave missed a packet).
+	case C_MASTER: // Our master is wrong
+	    	return cluster_set_master(addr, more);
+
+	case C_LASTSEEN: // Catch up a slave (slave missed a packet).
 		return cluster_catchup_slave(more, addr);
 
 	case C_FORWARD: { // Forwarded control packet. pass off to processudp.
@@ -1452,6 +1475,11 @@ int processcluster(char *data, int size, in_addr_t addr)
 		return 0;
 
 	case C_BYTES:
+		if (!config->cluster_iam_master) {
+			LOG(0, 0, 0, "I'm not the master, but I got a C_BYTES from %s?\n", fmtaddr(addr, 0));
+			return -1;
+		}
+
 		return cluster_handle_bytes(p, s);
 
 	case C_KILL:	// The master asked us to die!? (usually because we're too out of date).