[pve-ha-manager.git] / src / PVE / HA / LRM.pm

package PVE::HA::LRM;

# Local Resource Manager

use strict;
use warnings;
use Data::Dumper;
use POSIX qw(:sys_wait_h);

use PVE::SafeSyslog;
use PVE::Tools;
use PVE::HA::Tools;

# Server can have several states:

my $valid_states = {
    wait_for_agent_lock => "waiting for agent lock",
    active => "got agent_lock",
    lost_agent_lock => "lost agent_lock",
};

sub new {
    my ($this, $haenv) = @_;

    my $class = ref($this) || $this;

    my $self = bless {
	haenv => $haenv,
	status => { state => 'startup' },
	workers => {},
	results => {},
	shutdown_request => 0,
    }, $class;

    $self->set_local_status({ state => 	'wait_for_agent_lock' });   
    
    return $self;
}

sub shutdown_request {
    my ($self) = @_;

    $self->{shutdown_request} = 1;
}

sub get_local_status {
    my ($self) = @_;

    return $self->{status};
}

sub set_local_status {
    my ($self, $new) = @_;

    die "invalid state '$new->{state}'" if !$valid_states->{$new->{state}};

    my $haenv = $self->{haenv};

    my $old = $self->{status};

    # important: only update if if really changed 
    return if $old->{state} eq $new->{state};

    $haenv->log('info', "status change $old->{state} => $new->{state}");

    $new->{state_change_time} = $haenv->get_time();

    $self->{status} = $new;
}

sub get_protected_ha_agent_lock {
    my ($self) = @_;

    my $haenv = $self->{haenv};

    my $count = 0;
    my $starttime = $haenv->get_time();

    for (;;) {
	
	if ($haenv->get_ha_agent_lock()) {
	    if ($self->{ha_agent_wd}) {
		$haenv->watchdog_update($self->{ha_agent_wd});
	    } else {
		my $wfh = $haenv->watchdog_open();
		$self->{ha_agent_wd} = $wfh;
	    }
	    return 1;
	}
	    
	last if ++$count > 5; # try max 5 time

	my $delay = $haenv->get_time() - $starttime;
	last if $delay > 5; # for max 5 seconds

	$haenv->sleep(1);
    }
    
    return 0;
}

sub fenced_service_count {
    my ($self) = @_;
    
    my $haenv = $self->{haenv};

    my $nodename = $haenv->nodename();

    my $ss = $self->{service_status};

    my $count = 0;
    
    foreach my $sid (keys %$ss) {
	my $sd = $ss->{$sid};
	next if !$sd->{node};
	next if $sd->{node} ne $nodename;
	my $req_state = $sd->{state};
	next if !defined($req_state);
	if ($req_state eq 'fence') {
	    $count++;
	    next;
	}
    }
    
    return $count;
}
    
sub do_one_iteration {
    my ($self) = @_;

    my $haenv = $self->{haenv};

    my $status = $self->get_local_status();
    my $state = $status->{state};

    my $ms = $haenv->read_manager_status();
    $self->{service_status} =  $ms->{service_status} || {};

    my $fence_request = $self->fenced_service_count();
    
    # do state changes first 

    my $ctime = $haenv->get_time();

    if ($state eq 'wait_for_agent_lock') {

	my $service_count = 1; # todo: correctly compute

	if (!$fence_request && $service_count && $haenv->quorate()) {
	    if ($self->get_protected_ha_agent_lock()) {
		$self->set_local_status({ state => 'active' });
	    }
	}
	
    } elsif ($state eq 'lost_agent_lock') {

	if (!$fence_request && $haenv->quorate()) {
	    if ($self->get_protected_ha_agent_lock()) {
		$self->set_local_status({ state => 'active' });
	    }
	}

    } elsif ($state eq 'active') {

	if ($fence_request) {		
	    $haenv->log('err', "node need to be fenced - releasing agent_lock\n");
	    $self->set_local_status({ state => 'lost_agent_lock'});	
	} elsif (!$self->get_protected_ha_agent_lock()) {
	    $self->set_local_status({ state => 'lost_agent_lock'});
	}
    }

    $status = $self->get_local_status();
    $state = $status->{state};

    # do work

    if ($state eq 'wait_for_agent_lock') {

	return 0 if $self->{shutdown_request};

	$haenv->sleep(5);
	   
    } elsif ($state eq 'active') {

	my $startime = $haenv->get_time();

	my $max_time = 10;

	my $shutdown = 0;

	# do work (max_time seconds)
	eval {
	    # fixme: set alert timer

	    if ($self->{shutdown_request}) {

		# fixme: request service stop or relocate ?

		my $service_count = 0; # fixme

		if ($service_count == 0) {

		    if ($self->{ha_agent_wd}) {
			$haenv->watchdog_close($self->{ha_agent_wd});
			delete $self->{ha_agent_wd};
		    }

		    $shutdown = 1;
		}
	    } else {

		$self->manage_resources();

	    }
	};
	if (my $err = $@) {
	    $haenv->log('err', "got unexpected error - $err");
	}

	return 0 if $shutdown;

	$haenv->sleep_until($startime + $max_time);

    } elsif ($state eq 'lost_agent_lock') {
	
	# Note: watchdog is active an will triger soon!

	# so we hope to get the lock back soon!

	if ($self->{shutdown_request}) {

	    my $running_services = 0; # fixme: correctly compute

	    if ($running_services > 0) {
		$haenv->log('err', "get shutdown request in state 'lost_agent_lock' - " . 
			    "killing running services");

		# fixme: kill all services as fast as possible
	    }

	    # now all services are stopped, so we can close the watchdog

	    if ($self->{ha_agent_wd}) {
		$haenv->watchdog_close($self->{ha_agent_wd});
		delete $self->{ha_agent_wd};
	    }

	    return 0;
	}

	$haenv->sleep(5);

    } else {

	die "got unexpected status '$state'\n";

    }

    return 1;
}

sub manage_resources {
    my ($self) = @_;

    my $haenv = $self->{haenv};

    my $nodename = $haenv->nodename();

    my $ss = $self->{service_status};

    foreach my $sid (keys %$ss) {
	my $sd = $ss->{$sid};
	next if !$sd->{node};
	next if !$sd->{uid};
	next if $sd->{node} ne $nodename;
	my $req_state = $sd->{state};
	next if !defined($req_state);
	eval {
	    $self->queue_resource_command($sid, $sd->{uid}, $req_state, $sd->{target});
	};
	if (my $err = $@) {
	    warn "unable to run resource agent for '$sid' - $err"; # fixme
	}
    }

    my $starttime = time();

    # start workers
    my $max_workers = 4;

    my $sc = $haenv->read_service_config();
    
    while ((time() - $starttime) < 5) {
	my $count =  $self->check_active_workers();

	foreach my $sid (keys %{$self->{workers}}) {
	    last if $count >= $max_workers;
	    my $w = $self->{workers}->{$sid};
	    my $cd = $sc->{$sid};
	    if (!$cd) {
		warn "missing resource configuration for '$sid'\n";
		next;
	    }
	    if (!$w->{pid}) {
		my $pid = fork();
		if (!defined($pid)) {
		    warn "fork worker failed\n";
		    $count = 0; last; # abort, try later
		} elsif ($pid == 0) {
		    # do work
		    my $res = -1;
		    eval {
			$res = $haenv->exec_resource_agent($sid, $cd, $w->{state}, $w->{target});
		    };
		    if (my $err = $@) {
			warn $err;
			POSIX::_exit(-1);
		    }  
		    POSIX::_exit($res); 
		} else {
		    $count++;
		    $w->{pid} = $pid;
		}
	    }
	}

	last if !$count;

	sleep(1);
    }
}

# fixme: use a queue an limit number of parallel workers?
sub queue_resource_command {
    my ($self, $sid, $uid, $state, $target) = @_;

    if (my $w = $self->{workers}->{$sid}) {
	return if $w->{pid}; # already started
	# else, delete and overwrite queue entry with new command
	delete $self->{workers}->{$sid};
    }

    $self->{workers}->{$sid} = {
	sid => $sid,
	uid => $uid,
	state => $state,
    };

    $self->{workers}->{$sid}->{target} = $target if $target;
}

sub check_active_workers {
    my ($self) = @_;

    # finish/count workers
    my $count = 0;
    foreach my $sid (keys %{$self->{workers}}) {
	my $w = $self->{workers}->{$sid};
	if (my $pid = $w->{pid}) {
	    # check status
	    my $waitpid = waitpid($pid, WNOHANG);
	    if (defined($waitpid) && ($waitpid == $pid)) {
		$self->resource_command_finished($sid, $w->{uid}, $?);
	    } else {
		$count++;
	    }
	}
    }
    
    return $count;
}

sub resource_command_finished {
    my ($self, $sid, $uid, $status) = @_;

    my $haenv = $self->{haenv};

    my $w = delete $self->{workers}->{$sid};
    return if !$w; # should not happen

    my $exit_code = -1;

    if ($status == -1) {
	$haenv->log('err', "resource agent $sid finished - failed to execute");    
    }  elsif (my $sig = ($status & 127)) {
	$haenv->log('err', "resource agent $sid finished - got signal $sig");
    } else {
	$exit_code = ($status >> 8);
    }

    $self->{results}->{$uid} = {
	sid => $w->{sid},
	state => $w->{state},
	exit_code => $exit_code,
    };

    my $ss = $self->{service_status};

    # compute hash of valid/existing uids
    my $valid_uids = {};
    foreach my $sid (keys %$ss) {
	my $sd = $ss->{$sid};
	next if !$sd->{uid};
	$valid_uids->{$sd->{uid}} = 1;
    }

    my $results = {};
    foreach my $id (keys %{$self->{results}}) {
	next if !$valid_uids->{$id};
	$results->{$id} = $self->{results}->{$id};
    }
    $self->{results} = $results;

    $haenv->write_lrm_status($results);
}

1;
Commit	Line	Data
5f095798 DM	1	package PVE::HA::LRM;
	2
	3	# Local Resource Manager
	4
	5	use strict;
	6	use warnings;
c4a221bc DM	7	use Data::Dumper;
c4a221bc DM	8	use POSIX qw(:sys_wait_h);
5f095798 DM	9
	10	use PVE::SafeSyslog;
	11	use PVE::Tools;
	12	use PVE::HA::Tools;
	13
	14	# Server can have several states:
	15
	16	my $valid_states = {
ec911edd	17	wait_for_agent_lock => "waiting for agent lock",
0bba8f60	18	active => "got agent_lock",
5f095798 DM	19	lost_agent_lock => "lost agent_lock",
	20	};
	21
	22	sub new {
	23	my ($this, $haenv) = @_;
	24
	25	my $class = ref($this) \|\| $this;
	26
	27	my $self = bless {
	28	haenv => $haenv,
	29	status => { state => 'startup' },
c4a221bc DM	30	workers => {},
c4a221bc DM	31	results => {},
067cdf33	32	shutdown_request => 0,
5f095798 DM	33	}, $class;
5f095798 DM	34
b0bf08a9	35	$self->set_local_status({ state => 'wait_for_agent_lock' });
5f095798 DM	36
	37	return $self;
	38	}
	39
	40	sub shutdown_request {
	41	my ($self) = @_;
	42
	43	$self->{shutdown_request} = 1;
	44	}
	45
	46	sub get_local_status {
	47	my ($self) = @_;
	48
	49	return $self->{status};
	50	}
	51
	52	sub set_local_status {
	53	my ($self, $new) = @_;
	54
	55	die "invalid state '$new->{state}'" if !$valid_states->{$new->{state}};
	56
	57	my $haenv = $self->{haenv};
	58
	59	my $old = $self->{status};
	60
	61	# important: only update if if really changed
	62	return if $old->{state} eq $new->{state};
	63
0bba8f60	64	$haenv->log('info', "status change $old->{state} => $new->{state}");
5f095798 DM	65
	66	$new->{state_change_time} = $haenv->get_time();
	67
	68	$self->{status} = $new;
	69	}
	70
	71	sub get_protected_ha_agent_lock {
	72	my ($self) = @_;
	73
	74	my $haenv = $self->{haenv};
	75
	76	my $count = 0;
	77	my $starttime = $haenv->get_time();
	78
	79	for (;;) {
	80
	81	if ($haenv->get_ha_agent_lock()) {
	82	if ($self->{ha_agent_wd}) {
	83	$haenv->watchdog_update($self->{ha_agent_wd});
	84	} else {
	85	my $wfh = $haenv->watchdog_open();
	86	$self->{ha_agent_wd} = $wfh;
	87	}
	88	return 1;
	89	}
	90
	91	last if ++$count > 5; # try max 5 time
	92
	93	my $delay = $haenv->get_time() - $starttime;
	94	last if $delay > 5; # for max 5 seconds
	95
	96	$haenv->sleep(1);
	97	}
	98
	99	return 0;
	100	}
	101
067cdf33 DM	102	sub fenced_service_count {
	103	my ($self) = @_;
	104
	105	my $haenv = $self->{haenv};
	106
	107	my $nodename = $haenv->nodename();
	108
	109	my $ss = $self->{service_status};
	110
	111	my $count = 0;
	112
	113	foreach my $sid (keys %$ss) {
	114	my $sd = $ss->{$sid};
	115	next if !$sd->{node};
	116	next if $sd->{node} ne $nodename;
	117	my $req_state = $sd->{state};
	118	next if !defined($req_state);
	119	if ($req_state eq 'fence') {
	120	$count++;
	121	next;
	122	}
	123	}
	124
	125	return $count;
	126	}
	127
5f095798 DM	128	sub do_one_iteration {
	129	my ($self) = @_;
	130
	131	my $haenv = $self->{haenv};
	132
	133	my $status = $self->get_local_status();
	134	my $state = $status->{state};
	135
067cdf33 DM	136	my $ms = $haenv->read_manager_status();
	137	$self->{service_status} = $ms->{service_status} \|\| {};
	138
	139	my $fence_request = $self->fenced_service_count();
	140
5f095798 DM	141	# do state changes first
	142
	143	my $ctime = $haenv->get_time();
	144
b0bf08a9	145	if ($state eq 'wait_for_agent_lock') {
5f095798 DM	146
	147	my $service_count = 1; # todo: correctly compute
	148
067cdf33	149	if (!$fence_request && $service_count && $haenv->quorate()) {
0bba8f60 DM	150	if ($self->get_protected_ha_agent_lock()) {
0bba8f60 DM	151	$self->set_local_status({ state => 'active' });
5f095798 DM	152	}
	153	}
	154
	155	} elsif ($state eq 'lost_agent_lock') {
	156
067cdf33	157	if (!$fence_request && $haenv->quorate()) {
0bba8f60 DM	158	if ($self->get_protected_ha_agent_lock()) {
0bba8f60 DM	159	$self->set_local_status({ state => 'active' });
5f095798 DM	160	}
	161	}
	162
0bba8f60	163	} elsif ($state eq 'active') {
5f095798	164
067cdf33 DM	165	if ($fence_request) {
	166	$haenv->log('err', "node need to be fenced - releasing agent_lock\n");
	167	$self->set_local_status({ state => 'lost_agent_lock'});
	168	} elsif (!$self->get_protected_ha_agent_lock()) {
5f095798 DM	169	$self->set_local_status({ state => 'lost_agent_lock'});
	170	}
	171	}
	172
	173	$status = $self->get_local_status();
	174	$state = $status->{state};
	175
	176	# do work
	177
	178	if ($state eq 'wait_for_agent_lock') {
	179
	180	return 0 if $self->{shutdown_request};
	181
	182	$haenv->sleep(5);
	183
0bba8f60	184	} elsif ($state eq 'active') {
5f095798 DM	185
	186	my $startime = $haenv->get_time();
	187
	188	my $max_time = 10;
	189
	190	my $shutdown = 0;
	191
	192	# do work (max_time seconds)
	193	eval {
	194	# fixme: set alert timer
	195
	196	if ($self->{shutdown_request}) {
	197
	198	# fixme: request service stop or relocate ?
	199
	200	my $service_count = 0; # fixme
	201
	202	if ($service_count == 0) {
	203
	204	if ($self->{ha_agent_wd}) {
	205	$haenv->watchdog_close($self->{ha_agent_wd});
	206	delete $self->{ha_agent_wd};
	207	}
	208
	209	$shutdown = 1;
	210	}
c4a221bc	211	} else {
c4a221bc DM	212
c4a221bc DM	213	$self->manage_resources();
067cdf33	214
5f095798 DM	215	}
	216	};
	217	if (my $err = $@) {
	218	$haenv->log('err', "got unexpected error - $err");
	219	}
	220
	221	return 0 if $shutdown;
	222
	223	$haenv->sleep_until($startime + $max_time);
	224
	225	} elsif ($state eq 'lost_agent_lock') {
	226
	227	# Note: watchdog is active an will triger soon!
	228
	229	# so we hope to get the lock back soon!
	230
	231	if ($self->{shutdown_request}) {
	232
	233	my $running_services = 0; # fixme: correctly compute
	234
	235	if ($running_services > 0) {
	236	$haenv->log('err', "get shutdown request in state 'lost_agent_lock' - " .
	237	"killing running services");
	238
	239	# fixme: kill all services as fast as possible
	240	}
	241
	242	# now all services are stopped, so we can close the watchdog
	243
	244	if ($self->{ha_agent_wd}) {
	245	$haenv->watchdog_close($self->{ha_agent_wd});
	246	delete $self->{ha_agent_wd};
	247	}
	248
	249	return 0;
	250	}
	251
b0bf08a9 DM	252	$haenv->sleep(5);
b0bf08a9 DM	253
5f095798 DM	254	} else {
	255
	256	die "got unexpected status '$state'\n";
	257
	258	}
	259
	260	return 1;
	261	}
	262
c4a221bc DM	263	sub manage_resources {
	264	my ($self) = @_;
	265
	266	my $haenv = $self->{haenv};
	267
	268	my $nodename = $haenv->nodename();
	269
c4a221bc DM	270	my $ss = $self->{service_status};
	271
	272	foreach my $sid (keys %$ss) {
	273	my $sd = $ss->{$sid};
	274	next if !$sd->{node};
	275	next if !$sd->{uid};
	276	next if $sd->{node} ne $nodename;
	277	my $req_state = $sd->{state};
	278	next if !defined($req_state);
c4a221bc	279	eval {
e88469ba	280	$self->queue_resource_command($sid, $sd->{uid}, $req_state, $sd->{target});
c4a221bc DM	281	};
	282	if (my $err = $@) {
	283	warn "unable to run resource agent for '$sid' - $err"; # fixme
	284	}
	285	}
	286
	287	my $starttime = time();
	288
	289	# start workers
	290	my $max_workers = 4;
	291
6dbf93a0 DM	292	my $sc = $haenv->read_service_config();
6dbf93a0 DM	293
c4a221bc DM	294	while ((time() - $starttime) < 5) {
	295	my $count = $self->check_active_workers();
	296
	297	foreach my $sid (keys %{$self->{workers}}) {
	298	last if $count >= $max_workers;
	299	my $w = $self->{workers}->{$sid};
6dbf93a0 DM	300	my $cd = $sc->{$sid};
	301	if (!$cd) {
	302	warn "missing resource configuration for '$sid'\n";
	303	next;
	304	}
c4a221bc DM	305	if (!$w->{pid}) {
	306	my $pid = fork();
	307	if (!defined($pid)) {
	308	warn "fork worker failed\n";
	309	$count = 0; last; # abort, try later
	310	} elsif ($pid == 0) {
	311	# do work
	312	my $res = -1;
	313	eval {
6dbf93a0	314	$res = $haenv->exec_resource_agent($sid, $cd, $w->{state}, $w->{target});
c4a221bc DM	315	};
	316	if (my $err = $@) {
	317	warn $err;
	318	POSIX::_exit(-1);
	319	}
	320	POSIX::_exit($res);
	321	} else {
	322	$count++;
	323	$w->{pid} = $pid;
	324	}
	325	}
	326	}
	327
	328	last if !$count;
	329
	330	sleep(1);
	331	}
	332	}
	333
	334	# fixme: use a queue an limit number of parallel workers?
	335	sub queue_resource_command {
e88469ba	336	my ($self, $sid, $uid, $state, $target) = @_;
c4a221bc DM	337
	338	if (my $w = $self->{workers}->{$sid}) {
	339	return if $w->{pid}; # already started
	340	# else, delete and overwrite queue entry with new command
	341	delete $self->{workers}->{$sid};
	342	}
	343
	344	$self->{workers}->{$sid} = {
	345	sid => $sid,
	346	uid => $uid,
	347	state => $state,
	348	};
e88469ba DM	349
e88469ba DM	350	$self->{workers}->{$sid}->{target} = $target if $target;
c4a221bc DM	351	}
	352
	353	sub check_active_workers {
	354	my ($self) = @_;
	355
	356	# finish/count workers
	357	my $count = 0;
	358	foreach my $sid (keys %{$self->{workers}}) {
	359	my $w = $self->{workers}->{$sid};
	360	if (my $pid = $w->{pid}) {
	361	# check status
	362	my $waitpid = waitpid($pid, WNOHANG);
	363	if (defined($waitpid) && ($waitpid == $pid)) {
	364	$self->resource_command_finished($sid, $w->{uid}, $?);
	365	} else {
	366	$count++;
	367	}
	368	}
	369	}
	370
	371	return $count;
	372	}
	373
	374	sub resource_command_finished {
	375	my ($self, $sid, $uid, $status) = @_;
	376
	377	my $haenv = $self->{haenv};
	378
	379	my $w = delete $self->{workers}->{$sid};
	380	return if !$w; # should not happen
	381
	382	my $exit_code = -1;
	383
	384	if ($status == -1) {
0f70400d	385	$haenv->log('err', "resource agent $sid finished - failed to execute");
c4a221bc	386	} elsif (my $sig = ($status & 127)) {
0f70400d	387	$haenv->log('err', "resource agent $sid finished - got signal $sig");
c4a221bc DM	388	} else {
c4a221bc DM	389	$exit_code = ($status >> 8);
c4a221bc DM	390	}
	391
	392	$self->{results}->{$uid} = {
	393	sid => $w->{sid},
	394	state => $w->{state},
	395	exit_code => $exit_code,
	396	};
	397
	398	my $ss = $self->{service_status};
	399
	400	# compute hash of valid/existing uids
	401	my $valid_uids = {};
	402	foreach my $sid (keys %$ss) {
	403	my $sd = $ss->{$sid};
	404	next if !$sd->{uid};
	405	$valid_uids->{$sd->{uid}} = 1;
	406	}
	407
	408	my $results = {};
	409	foreach my $id (keys %{$self->{results}}) {
	410	next if !$valid_uids->{$id};
	411	$results->{$id} = $self->{results}->{$id};
	412	}
	413	$self->{results} = $results;
	414
	415	$haenv->write_lrm_status($results);
	416	}
	417
5f095798	418	1;