Merge lp:~seuis398/mysql-mmm/reliable_virtual_ip into lp:mysql-mmm

[SeWoong Jeon]

Because there is a limit to the number of arp packet a switch can handle simultaneously, MMM arp packets can be ignored sometimes.
In that case, client host cannot access mysql db through virtual ip, because of wrong arp cache.
So, arp packet send interval need to be increased.

And... to make sure virtual ip is assigned exactly,
mmm_control executes "vip ping test" and displays the result. ("Net::Ping" is required.)

(Ex.) $ mmm_control show
  db01(192.168.56.10) master/ONLINE. Roles: writer(192.168.56.20)/Ping_OK
  db02(192.168.56.11) master/ONLINE. Roles: reader(192.168.56.21)/Ping_Error

Unmerged revisions

149. By SeWoong Jeon on 2012-02-02

To make sure vip is assigned exactly,
mmm_control executes "vip ping test" and displays the result.
"Net::Ping" is required.

(Ex.) $ mmm_control show
  db01(192.168.56.10) master/ONLINE. Roles: writer(192.168.56.20)/Ping_OK
  db02(192.168.56.11) master/ONLINE. Roles: reader(192.168.56.21)/Ping_Error

148. By SeWoong Jeon on 2012-02-01

Because there is a limit to the number of arp packet switch can handle simultaneously,
MMM arp packets can be ignored sometimes.
In that case, client host cannot access mysql db through virtual ip, because of wrong arp cache.

=== modified file 'lib/Agent/Helpers/Network.pm'
--- lib/Agent/Helpers/Network.pm	2010-02-05 17:27:32 +0000
+++ lib/Agent/Helpers/Network.pm	2012-02-07 10:31:03 +0000
@@ -141,11 +141,11 @@
 		}
 		return "ERROR: Couldn't get mac adress of interface $if" unless ($mac);
 
-		for (my $i = 0; $i < 5; $i++) {
+		for (my $i = 0; $i < 10; $i++) {
 			Net::ARP::send_packet($if, $ip, $ip, $mac, 'ff:ff:ff:ff:ff:ff', 'request');
 			usleep(50);
 			Net::ARP::send_packet($if, $ip, $ip, $mac, 'ff:ff:ff:ff:ff:ff', 'reply');
-			usleep(50) if ($i < 4);
+			sleep(1) if ($i < 9);
 		}
 	}
 	elsif ($OSNAME eq 'solaris') {

=== modified file 'lib/Monitor/Agents.pm'
--- lib/Monitor/Agents.pm	2009-06-11 07:10:36 +0000
+++ lib/Monitor/Agents.pm	2012-02-07 10:31:03 +0000
@@ -9,7 +9,7 @@
 use File::Basename;
 use MMM::Monitor::Agent;
 use MMM::Monitor::Role;
-
+use Net::Ping;
 
 
 
@@ -131,14 +131,29 @@
 	my $detailed= shift || 0;
 	my $res		= '';
 	my $agent_res = '';
+	my $p = Net::Ping->new("tcp");
 
 	keys (%$self); # reset iterator
 	foreach my $host (sort(keys(%$self))) {
 		my $agent = $self->{$host};
 		next unless $agent;
 		$agent_res	.= "# Warning: agent on host $host is not reachable\n" if ($agent->agent_down());
-		$res		.= sprintf("  %s(%s) %s/%s. Roles: %s\n", $host, $agent->ip, $agent->mode, $agent->state, join(', ', sort(@{$agent->roles})));
+
+		my @arr_role;
+		foreach my $check_roles (@{$agent->roles}) {
+			$check_roles =~ /(writer|reader)\((.*)\)/;
+			my $vip = $2;
+			my $ping_check = "Error";
+			$ping_check = "OK" if $p->ping($vip, 1);
+
+			unshift @arr_role, sprintf("%s/Ping_%s", $check_roles, $ping_check);
+		}
+
+		$res .= sprintf("  %s(%s) %s/%s. Roles: %s\n", $host, join(':', $agent->ip, $agent->mysql_port), $agent->mode, $agent->state, join(', ', sort(@arr_role)));
 	}
+
+	$p->close();
+
 	$res = $agent_res . $res if ($detailed);
 	return $res;
 }