--- loncom/loncnew 2003/10/27 10:09:21 1.30
+++ loncom/loncnew 2006/08/25 21:12:19 1.76
@@ -2,7 +2,7 @@
# The LearningOnline Network with CAPA
# lonc maintains the connections to remote computers
#
-# $Id: loncnew,v 1.30 2003/10/27 10:09:21 foxr Exp $
+# $Id: loncnew,v 1.76 2006/08/25 21:12:19 albertel Exp $
#
# Copyright Michigan State University Board of Trustees
#
@@ -35,118 +35,16 @@
# - Add ability to create/negotiate lond connections (done).
# - Add general logic for dispatching requests and timeouts. (done).
# - Add support for the lonc/lond requests. (done).
-# - Add logging/status monitoring.
-# - Add Signal handling - HUP restarts. USR1 status report.
+# - Add logging/status monitoring. (done)
+# - Add Signal handling - HUP restarts. USR1 status report. (done)
# - Add Configuration file I/O (done).
-# - Add management/status request interface.
+# - Add management/status request interface. (done)
# - Add deferred request capability. (done)
-# - Detect transmission timeouts.
+# - Detect transmission timeouts. (done)
#
-# Change log:
-# $Log: loncnew,v $
-# Revision 1.30 2003/10/27 10:09:21 foxr
-# Tighten up a few compares to eq and flip a few debug levels around... nothing
-# critical
-#
-# Revision 1.29 2003/10/21 14:24:42 foxr
-# Fix little typo that may explain growth of connections
-#
-# Revision 1.28 2003/10/14 15:36:21 albertel
-# - making it easier to run loncnew,
-# /etc/init.d/loncontrol startnew
-# /etc/init.d/loncontrol restartnew
-# will now start loncnew in place of lonc
-#
-# Revision 1.27 2003/10/07 11:23:03 foxr
-# Installed and tested code to process reinit in parent server.
-#
-# Revision 1.26 2003/09/30 11:11:17 foxr
-# Add book-keeping hashes to support the re-init procedure.
-#
-# Revision 1.25 2003/09/23 11:22:14 foxr
-# Tested ability to receive sigusr2 This is now logged and must be
-# properly implemented as a re-read of hosts and re-init of appropriate
-# children.
-#
-# Revision 1.24 2003/09/16 09:46:42 foxr
-# Added skeletal infrastructure to support SIGUSR2 update hosts request.
-#
-# Revision 1.23 2003/09/15 09:24:49 foxr
-# Add use strict and fix all the fallout from that.
-#
-# Revision 1.22 2003/09/02 10:34:47 foxr
-# - Fix errors in host dead detection logic (too many cases where the
-# retries left were not getting incremented or just not checked).
-# - Added some additional status to the ps axuww display:
-# o Remaining retries on a host.
-# o >>> DEAD <<< indicator if I've given up on a host.
-# - Tested the SIGHUP will reset the retries remaining count (thanks to
-# the above status stuff, and get allow the loncnew to re-try again
-# on the host (thanks to the log).
-#
-# Revision 1.21 2003/08/26 09:19:51 foxr
-# How embarrassing... put in the SocketTimeout function in loncnew and forgot
-# to actually hook it into the LondTransaction. Added this to MakeLondConnection
-# where it belongs... hopefully transactions (not just connection attempts) will
-# timeout more speedily than the socket errors will catch it.
-#
-# Revision 1.20 2003/08/25 18:48:11 albertel
-# - fixing a forgotten ;
-#
-# Revision 1.19 2003/08/19 09:31:46 foxr
-# Get socket directory from configuration rather than the old hard coded test
-# way that I forgot to un-hard code.
-#
-# Revision 1.18 2003/08/06 09:52:29 foxr
-# Also needed to remember to fail in-flight transactions if their sends fail.
-#
-# Revision 1.17 2003/08/03 00:44:31 foxr
-# 1. Correct handling of connection failure: Assume it means the host is
-# unreachable and fail all of the queued transactions. Note that the
-# inflight transactions should fail on their own time due either to timeout
-# or send/receive failures.
-# 2. Correct handling of logs for forced death signals. Pull the signal
-# from the event watcher.
-#
-# Revision 1.16 2003/07/29 02:33:05 foxr
-# Add SIGINT processing to child processes to toggle annoying trace mode
-# on/off.. will try to use this to isolate the compute boud process issue.
-#
-# Revision 1.15 2003/07/15 02:07:05 foxr
-# Added code for lonc/lond transaction timeouts. Who knows if it works right.
-# The intent is for a timeout to fail any transaction in progress and kill
-# off the sockt that timed out.
-#
-# Revision 1.14 2003/07/03 02:10:18 foxr
-# Get all of the signals to work correctly.
-#
-# Revision 1.13 2003/07/02 01:31:55 foxr
-# Added kill -HUP logic (restart).
-#
-# Revision 1.11 2003/06/25 01:54:44 foxr
-# Fix more problems with transaction failure.
-#
-# Revision 1.10 2003/06/24 02:46:04 foxr
-# Put a limit on the number of times we'll retry a connection.
-# Start getting the signal stuff put in as well...note that need to get signals
-# going or else the client will permanently give up on dead servers.
-#
-# Revision 1.9 2003/06/13 02:38:43 foxr
-# Add logging in 'expected format'
-#
-# Revision 1.8 2003/06/11 02:04:35 foxr
-# Support delayed transactions... this is done uniformly by encapsulating
-# transactions in an object ... a LondTransaction that is implemented by
-# LondTransaction.pm
-#
-# Revision 1.7 2003/06/03 01:59:39 foxr
-# complete coding to support deferred transactions.
-#
-#
use strict;
use lib "/home/httpd/lib/perl/";
-use lib "/home/foxr/newloncapa/types";
use Event qw(:DEFAULT );
use POSIX qw(:signal_h);
use POSIX;
@@ -163,11 +61,7 @@ use LONCAPA::LondConnection;
use LONCAPA::LondTransaction;
use LONCAPA::Configuration;
use LONCAPA::HashIterator;
-
-
-#
-# Disable all signals we might receive from outside for now.
-#
+use Fcntl qw(:flock);
# Read the httpd configuration file to get perl variables
@@ -182,14 +76,21 @@ my %perlvar = %{$perlvarref};
my %ChildHash; # by pid -> host.
my %HostToPid; # By host -> pid.
my %HostHash; # by loncapaname -> IP.
+my %listening_to; # Socket->host table for who the parent
+ # is listening to.
+my %parent_dispatchers; # host-> listener watcher events.
+my %parent_handlers; # Parent signal handlers...
my $MaxConnectionCount = 10; # Will get from config later.
my $ClientConnection = 0; # Uniquifier for client events.
my $DebugLevel = 0;
my $NextDebugLevel= 2; # So Sigint can toggle this.
-my $IdleTimeout= 3600; # Wait an hour before pruning connections.
+my $IdleTimeout= 600; # Wait 10 minutes before pruning connections.
+
+my $LogTransactions = 0; # When True, all transactions/replies get logged.
+my $executable = $0; # Get the full path to me.
#
# The variables below are only used by the child processes.
@@ -205,8 +106,16 @@ my $ConnectionCount = 0;
my $IdleSeconds = 0; # Number of seconds idle.
my $Status = ""; # Current status string.
my $RecentLogEntry = "";
-my $ConnectionRetries=2; # Number of connection retries allowed.
-my $ConnectionRetriesLeft=2; # Number of connection retries remaining.
+my $ConnectionRetries=5; # Number of connection retries allowed.
+my $ConnectionRetriesLeft=5; # Number of connection retries remaining.
+my $LondVersion = "unknown"; # Version of lond we talk with.
+my $KeyMode = ""; # e.g. ssl, local, insecure from last connect.
+my $LondConnecting = 0; # True when a connection is being built.
+
+
+
+my $DieWhenIdle = 1; # When true children die when trimmed -> 0.
+my $I_am_child = 0; # True if this is the child process.
#
# The hash below gives the HTML format for log messages
@@ -214,13 +123,27 @@ my $ConnectionRetriesLeft=2; # Number of
#
my %LogFormats;
-$LogFormats{"CRITICAL"} = "CRITICAL: %s";
-$LogFormats{"SUCCESS"} = "SUCCESS: %s";
-$LogFormats{"INFO"} = "INFO: %s";
-$LogFormats{"WARNING"} = "WARNING: %s";
+$LogFormats{"CRITICAL"} = "CRITICAL: %s";
+$LogFormats{"SUCCESS"} = "SUCCESS: %s";
+$LogFormats{"INFO"} = "INFO: %s";
+$LogFormats{"WARNING"} = "WARNING: %s";
$LogFormats{"DEFAULT"} = " %s ";
+# UpdateStatus;
+# Update the idle status display to show how many connections
+# are left, retries and other stuff.
+#
+sub UpdateStatus {
+ if ($ConnectionRetriesLeft > 0) {
+ ShowStatus(GetServerHost()." Connection count: ".$ConnectionCount
+ ." Retries remaining: ".$ConnectionRetriesLeft
+ ." ($KeyMode)");
+ } else {
+ ShowStatus(GetServerHost()." >> DEAD <<");
+ }
+}
+
=pod
@@ -229,6 +152,7 @@ $LogFormats{"DEFAULT"} = " %s ";
Makes an entry into the permanent log file.
=cut
+
sub LogPerm {
my $message=shift;
my $execdir=$perlvar{'lonDaemons'};
@@ -260,9 +184,9 @@ host and the time will be formatted into
=cut
sub Log {
- my $severity = shift;
- my $message = shift;
-
+
+ my ($severity, $message) = @_;
+
if(!$LogFormats{$severity}) {
$severity = "DEFAULT";
}
@@ -274,7 +198,7 @@ sub Log {
my $now = time;
my $local = localtime($now);
my $finalformat = "$local ($$) [$RemoteHost] [$Status] ";
- my $finalformat = $finalformat.$format."\n";
+ $finalformat = $finalformat.$format."\n";
# open the file and put the result.
@@ -297,8 +221,10 @@ Returns the name of the host that a sock
=cut
sub GetPeername {
- my $connection = shift;
- my $AdrFamily = shift;
+
+
+ my ($connection, $AdrFamily) = @_;
+
my $peer = $connection->peername();
my $peerport;
my $peerip;
@@ -312,7 +238,6 @@ sub GetPeername {
return $peerfile;
}
}
-#----------------------------- Timer management ------------------------
=pod
=head2 Debug
@@ -322,18 +247,20 @@ Invoked to issue a debug message.
=cut
sub Debug {
- my $level = shift;
- my $message = shift;
+
+ my ($level, $message) = @_;
+
if ($level <= $DebugLevel) {
Log("INFO", "-Debug- $message host = $RemoteHost");
}
}
sub SocketDump {
- my $level = shift;
- my $socket= shift;
+
+ my ($level, $socket) = @_;
+
if($level <= $DebugLevel) {
- $socket->Dump();
+ $socket->Dump(-1); # Ensure it will get dumped.
}
}
@@ -345,6 +272,7 @@ sub SocketDump {
and as what we return in a SIGUSR1
=cut
+
sub ShowStatus {
my $state = shift;
my $now = time;
@@ -355,20 +283,70 @@ sub ShowStatus {
=pod
-=head 2 SocketTimeout
+=head2 SocketTimeout
Called when an action on the socket times out. The socket is
destroyed and any active transaction is failed.
=cut
+
sub SocketTimeout {
my $Socket = shift;
-
+ Log("WARNING", "A socket timeout was detected");
+ Debug(5, " SocketTimeout called: ");
+ $Socket->Dump(0);
+ if(exists($ActiveTransactions{$Socket})) {
+ FailTransaction($ActiveTransactions{$Socket});
+ }
KillSocket($Socket); # A transaction timeout also counts as
# a connection failure:
$ConnectionRetriesLeft--;
+ if($ConnectionRetriesLeft <= 0) {
+ Log("CRITICAL", "Host marked DEAD: ".GetServerHost());
+ $LondConnecting = 0;
+ }
+
+}
+#
+# This function should be called by the child in all cases where it must
+# exit. If the child process is running with the DieWhenIdle turned on
+# it must create a lock file for the AF_UNIX socket in order to prevent
+# connection requests from lonnet in the time between process exit
+# and the parent picking up the listen again.
+# Parameters:
+# exit_code - Exit status value, however see the next parameter.
+# message - If this optional parameter is supplied, the exit
+# is via a die with this message.
+#
+sub child_exit {
+ my ($exit_code, $message) = @_;
+
+ # Regardless of how we exit, we may need to do the lock thing:
+
+ if($DieWhenIdle) {
+ #
+ # Create a lock file since there will be a time window
+ # between our exit and the parent's picking up the listen
+ # during which no listens will be done on the
+ # lonnet client socket.
+ #
+ my $lock_file = GetLoncSocketPath().".lock";
+ open(LOCK,">$lock_file");
+ print LOCK "Contents not important";
+ close(LOCK);
+
+ exit(0);
+ }
+ # Now figure out how we exit:
+
+ if($message) {
+ die $message;
+ } else {
+ exit($exit_code);
+ }
}
+#----------------------------- Timer management ------------------------
=pod
@@ -380,13 +358,12 @@ Invoked each timer tick.
sub Tick {
+ my ($Event) = @_;
+ my $clock_watcher = $Event->w;
+
my $client;
- if($ConnectionRetriesLeft > 0) {
- ShowStatus(GetServerHost()." Connection count: ".$ConnectionCount
- ." Retries remaining: ".$ConnectionRetriesLeft);
- } else {
- ShowStatus(GetServerHost()." >> DEAD <<");
- }
+ UpdateStatus();
+
# Is it time to prune connection count:
@@ -396,6 +373,12 @@ sub Tick {
if($IdleSeconds > $IdleTimeout) { # Prune a connection...
my $Socket = $IdleConnections->pop();
KillSocket($Socket);
+ $IdleSeconds = 0; # Otherwise all connections get trimmed to fast.
+ UpdateStatus();
+ if(($ConnectionCount == 0) && $DieWhenIdle) {
+ &child_exit(0);
+
+ }
}
} else {
$IdleSeconds = 0; # Reset idle count if not idle.
@@ -403,35 +386,44 @@ sub Tick {
#
# For each inflight transaction, tick down its timeout counter.
#
- foreach my $item (keys %ActiveTransactions) {
- my $Socket = $ActiveTransactions{$item}->getServer();
- $Socket->Tick();
+
+ foreach my $item (keys %ActiveConnections) {
+ my $State = $ActiveConnections{$item}->data->GetState();
+ if ($State ne 'Idle') {
+ Debug(5,"Ticking Socket $State $item");
+ $ActiveConnections{$item}->data->Tick();
+ }
}
# Do we have work in the queue, but no connections to service them?
# If so, try to make some new connections to get things going again.
#
-
+ # Note this code is dead now...
+ #
my $Requests = $WorkQueue->Count();
- if (($ConnectionCount == 0) && ($Requests > 0)) {
+ if (($ConnectionCount == 0) && ($Requests > 0) && (!$LondConnecting)) {
if ($ConnectionRetriesLeft > 0) {
- my $Connections = ($Requests <= $MaxConnectionCount) ?
- $Requests : $MaxConnectionCount;
- Debug(5,"Work but no connections, start ".$Connections." of them");
- my $successCount = 0;
- for (my $i =0; $i < $Connections; $i++) {
- $successCount += MakeLondConnection();
- }
- if($successCount == 0) { # All connections failed:
+ Debug(5,"Work but no connections, Make a new one");
+ my $success;
+ $success = &MakeLondConnection;
+ if($success == 0) { # All connections failed:
Debug(5,"Work in queue failed to make any connectiouns\n");
EmptyQueue(); # Fail pending transactions with con_lost.
+ CloseAllLondConnections(); # Should all be closed but....
}
} else {
+ $LondConnecting = 0;
ShowStatus(GetServerHost()." >>> DEAD!!! <<<");
Debug(5,"Work in queue, but gave up on connections..flushing\n");
EmptyQueue(); # Connections can't be established.
+ CloseAllLondConnections(); # Should all already be closed but...
}
}
+ if ($ConnectionCount == 0) {
+ $KeyMode = "";
+ $clock_watcher->cancel();
+ }
+ &UpdateStatus();
}
=pod
@@ -452,7 +444,7 @@ Trigger disconnections of idle sockets.
sub SetupTimer {
Debug(6, "SetupTimer");
- Event->timer(interval => 1, debug => 1, cb => \&Tick );
+ Event->timer(interval => 1, cb => \&Tick );
}
=pod
@@ -472,6 +464,7 @@ long enough, it will be shut down and re
sub ServerToIdle {
my $Socket = shift; # Get the socket.
+ $KeyMode = $Socket->{AuthenticationMode};
delete($ActiveTransactions{$Socket}); # Server has no transaction
&Debug(5, "Server to idle");
@@ -551,7 +544,7 @@ sub ClientWritable {
} else { # Partial string sent.
$Watcher->data(substr($Data, $result));
if($result == 0) { # client hung up on us!!
- Log("INFO", "lonc pipe client hung up on us!");
+ # Log("INFO", "lonc pipe client hung up on us!");
$Watcher->cancel;
$Socket->shutdown(2);
$Socket->close();
@@ -604,11 +597,14 @@ The transaction that is being completed.
sub CompleteTransaction {
&Debug(5,"Complete transaction");
- my $Socket = shift;
- my $Transaction = shift;
+
+ my ($Socket, $Transaction) = @_;
if (!$Transaction->isDeferred()) { # Normal transaction
my $data = $Socket->GetReply(); # Data to send.
+ if($LogTransactions) {
+ Log("SUCCESS", "Reply from lond: '$data'");
+ }
StartClientReply($Transaction, $data);
} else { # Delete deferred transaction file.
Log("SUCCESS", "A delayed transaction was completed");
@@ -616,7 +612,9 @@ sub CompleteTransaction {
unlink $Transaction->getFile();
}
}
+
=pod
+
=head1 StartClientReply
Initiates a reply to a client where the reply data is a parameter.
@@ -632,10 +630,10 @@ sub CompleteTransaction {
The data to send to apached client.
=cut
+
sub StartClientReply {
- my $Transaction = shift;
- my $data = shift;
+ my ($Transaction, $data) = @_;
my $Client = $Transaction->getClient();
@@ -649,7 +647,9 @@ sub StartClientReply {
cb => \&ClientWritable,
data => $data);
}
+
=pod
+
=head2 FailTransaction
Finishes a transaction with failure because the associated lond socket
@@ -659,8 +659,7 @@ sub StartClientReply {
- The transaction is 'live' in which case we initiate the sending
of "con_lost" to the client.
-Deleting the transaction means killing it from the
-%ActiveTransactions hash.
+Deleting the transaction means killing it from the %ActiveTransactions hash.
Parameters:
@@ -668,30 +667,36 @@ Parameters:
The LondTransaction we are failing.
+
=cut
sub FailTransaction {
my $transaction = shift;
- Log("WARNING", "Failing transaction ".$transaction->getRequest());
- Debug(1, "Failing transaction: ".$transaction->getRequest());
+
+ # If the socket is dead, that's already logged.
+
+ if ($ConnectionRetriesLeft > 0) {
+ Log("WARNING", "Failing transaction "
+ .$transaction->getLoggableRequest());
+ }
+ Debug(1, "Failing transaction: ".$transaction->getLoggableRequest());
if (!$transaction->isDeferred()) { # If the transaction is deferred we'll get to it.
my $client = $transaction->getClient();
Debug(1," Replying con_lost to ".$transaction->getRequest());
StartClientReply($transaction, "con_lost\n");
}
- if($ConnectionRetriesLeft <= 0) {
- Log("CRITICAL", "Host marked dead: ".GetServerHost());
- }
}
=pod
+
=head1 EmptyQueue
Fails all items in the work queue with con_lost.
Note that each item in the work queue is a transaction.
=cut
+
sub EmptyQueue {
$ConnectionRetriesLeft--; # Counts as connection failure too.
while($WorkQueue->Count()) {
@@ -707,12 +712,15 @@ sub EmptyQueue {
Close all connections open on lond prior to exit e.g.
=cut
+
sub CloseAllLondConnections {
foreach my $Socket (keys %ActiveConnections) {
- KillSocket($Socket);
+ if(exists($ActiveTransactions{$Socket})) {
+ FailTransaction($ActiveTransactions{$Socket});
+ }
+ KillSocket($Socket);
}
}
-=cut
=pod
@@ -734,8 +742,8 @@ Parameters:
nonzero if we are allowed to create a new connection.
-
=cut
+
sub KillSocket {
my $Socket = shift;
@@ -753,14 +761,15 @@ sub KillSocket {
}
if(exists($ActiveConnections{$Socket})) {
delete($ActiveConnections{$Socket});
+ $ConnectionCount--;
+ if ($ConnectionCount < 0) { $ConnectionCount = 0; }
}
- $ConnectionCount--;
-
# If the connection count has gone to zero and there is work in the
# work queue, the work all gets failed with con_lost.
#
if($ConnectionCount == 0) {
EmptyQueue();
+ CloseAllLondConnections; # Should all already be closed but...
}
}
@@ -786,6 +795,17 @@ The connection must echo the challenge b
The challenge has been replied to. The we are receiveing the
'ok' from the partner.
+=head3 State=ReadingVersionString
+
+We have requested the lond version and are reading the
+version back. Upon completion, we'll store the version away
+for future use(?).
+
+=head3 State=HostSet
+
+We have selected the domain name of our peer (multhomed hosts)
+and are getting the reply (presumably ok) back.
+
=head3 State=RequestingKey
The ok has been received and we need to send the request for
@@ -840,13 +860,18 @@ sub LondReadable {
&Debug(2, "Socket->Readable returned: $status");
if($status != 0) {
- # bad return from socket read. Currently this means that
+ # bad return from socket read. Currently this means that
# The socket has become disconnected. We fail the transaction.
Log("WARNING",
"Lond connection lost.");
if(exists($ActiveTransactions{$Socket})) {
FailTransaction($ActiveTransactions{$Socket});
+ } else {
+ # Socket is connecting and failed... need to mark
+ # no longer connecting.
+
+ $LondConnecting = 0;
}
$Watcher->cancel();
KillSocket($Socket);
@@ -858,19 +883,34 @@ sub LondReadable {
$State = $Socket->GetState(); # Update in case of transition.
&Debug(6, "After read, state is ".$State);
- if($State eq "Initialized") {
+ if($State eq "Initialized") {
} elsif ($State eq "ChallengeReceived") {
# The challenge must be echoed back; The state machine
# in the connection takes care of setting that up. Just
# need to transition to writable:
-
+
$Watcher->cb(\&LondWritable);
$Watcher->poll("w");
} elsif ($State eq "ChallengeReplied") {
+ } elsif ($State eq "RequestingVersion") {
+ # Need to ask for the version... that is writiability:
+
+ $Watcher->cb(\&LondWritable);
+ $Watcher->poll("w");
+
+ } elsif ($State eq "ReadingVersionString") {
+ # Read the rest of the version string...
+ } elsif ($State eq "SetHost") {
+ # Need to request the actual domain get set...
+
+ $Watcher->cb(\&LondWritable);
+ $Watcher->poll("w");
+ } elsif ($State eq "HostSet") {
+ # Reading the 'ok' from the peer.
} elsif ($State eq "RequestingKey") {
# The ok was received. Now we need to request the key
@@ -882,6 +922,14 @@ sub LondReadable {
} elsif ($State eq "ReceivingKey") {
} elsif ($State eq "Idle") {
+
+ # This is as good a spot as any to get the peer version
+ # string:
+
+ if($LondVersion eq "unknown") {
+ $LondVersion = $Socket->PeerVersion();
+ Log("INFO", "Connected to lond version: $LondVersion");
+ }
# If necessary, complete a transaction and then go into the
# idle queue.
# Note that a trasition to idle indicates a live lond
@@ -898,12 +946,16 @@ sub LondReadable {
.$RemoteHost." now ready for action");
}
ServerToIdle($Socket); # Next work unit or idle.
+
+ #
+ $LondConnecting = 0; # Best spot I can think of for this.
+ #
} elsif ($State eq "SendingRequest") {
# We need to be writable for this and probably don't belong
# here inthe first place.
- Deubg(6, "SendingRequest state encountered in readable");
+ Debug(6, "SendingRequest state encountered in readable");
$Watcher->poll("w");
$Watcher->cb(\&LondWritable);
@@ -911,7 +963,7 @@ sub LondReadable {
} else {
- # Invalid state.
+ # Invalid state.
Debug(4, "Invalid state in LondReadable");
}
}
@@ -993,21 +1045,40 @@ sub LondWritable {
SocketDump(6,$Socket);
- if ($State eq "Connected") {
-
- if ($Socket->Writable() != 0) {
- # The write resulted in an error.
- # We'll treat this as if the socket got disconnected:
- Log("WARNING", "Connection to ".$RemoteHost.
- " has been disconnected");
+ # If the socket is writable, we must always write.
+ # Only by writing will we undergo state transitions.
+ # Old logic wrote in state specific code below, however
+ # That forces us at least through another invocation of
+ # this function after writability is possible again.
+ # This logic also factors out common code for handling
+ # write failures... in all cases, write failures
+ # Kill the socket.
+ # This logic makes the branches of the >big< if below
+ # so that the writing states are actually NO-OPs.
+
+ if ($Socket->Writable() != 0) {
+ # The write resulted in an error.
+ # We'll treat this as if the socket got disconnected:
+ Log("WARNING", "Connection to ".$RemoteHost.
+ " has been disconnected");
+ if(exists($ActiveTransactions{$Socket})) {
FailTransaction($ActiveTransactions{$Socket});
- $Watcher->cancel();
- KillSocket($Socket);
- return;
+ } else {
+ # In the process of conneting, so need to turn that off.
+
+ $LondConnecting = 0;
}
- # "init" is being sent...
+ $Watcher->cancel();
+ KillSocket($Socket);
+ return;
+ }
-
+
+
+ if ($State eq "Connected") {
+
+ # "init" is being sent...
+
} elsif ($State eq "Initialized") {
# Now that init was sent, we switch
@@ -1015,40 +1086,43 @@ sub LondWritable {
$Watcher->cb(\&LondReadable);
$Watcher->poll("r");
-
+
} elsif ($State eq "ChallengeReceived") {
# We received the challenge, now we
# are echoing it back. This is a no-op,
# we're waiting for the state to change
- if($Socket->Writable() != 0) {
-
- $Watcher->cancel();
- KillSocket($Socket);
- return;
- }
-
} elsif ($State eq "ChallengeReplied") {
# The echo was sent back, so we switch
# to watching readability.
$Watcher->cb(\&LondReadable);
$Watcher->poll("r");
+ } elsif ($State eq "RequestingVersion") {
+ # Sending the peer a version request...
+
+ } elsif ($State eq "ReadingVersionString") {
+ # Transition to read since we have sent the
+ # version command and now just need to read the
+ # version string from the peer:
+
+ $Watcher->cb(\&LondReadable);
+ $Watcher->poll("r");
+
+ } elsif ($State eq "SetHost") {
+ # Setting the remote domain...
+
+ } elsif ($State eq "HostSet") {
+ # Back to readable to get the ok.
+
+ $Watcher->cb(\&LondReadable);
+ $Watcher->poll("r");
+
} elsif ($State eq "RequestingKey") {
# At this time we're requesting the key.
# again, this is essentially a no-op.
- # we'll write the next chunk until the
- # state changes.
-
- if($Socket->Writable() != 0) {
- # Write resulted in an error.
- $Watcher->cancel();
- KillSocket($Socket);
- return;
-
- }
} elsif ($State eq "ReceivingKey") {
# Now we need to wait for the key
# to come back from the peer:
@@ -1057,20 +1131,10 @@ sub LondWritable {
$Watcher->poll("r");
} elsif ($State eq "SendingRequest") {
+
# At this time we are sending a request to the
# peer... write the next chunk:
- if($Socket->Writable() != 0) {
-
- if(exists($ActiveTransactions{$Socket})) {
- Debug(3, "Lond connection lost, failing transactions");
- FailTransaction($ActiveTransactions{$Socket});
- }
- $Watcher->cancel();
- KillSocket($Socket);
- return;
-
- }
} elsif ($State eq "ReceivingReply") {
# The send has completed. Wait for the
@@ -1092,6 +1156,7 @@ sub LondWritable {
=pod
=cut
+
sub QueueDelayed {
Debug(3,"QueueDelayed called");
@@ -1099,19 +1164,28 @@ sub QueueDelayed {
Debug(4, "Delayed path: ".$path);
opendir(DIRHANDLE, $path);
-
- my @alldelayed = grep /\.$RemoteHost$/, readdir DIRHANDLE;
+
+ my @all_host_ids;
+ my $host_iterator = &LondConnection::GetHostIterator();
+ while (!$host_iterator->end()) {
+ my ($host_id,$host_name) = @{$host_iterator->get()}[0,3];
+ if ($host_name eq $RemoteHost) {
+ push(@all_host_ids, $host_id);
+ }
+ $host_iterator->next();
+ }
+ my $host_id_re = '(?:'.join('|',@all_host_ids).')';
+ my @alldelayed = grep(/\.$host_id_re$/, readdir(DIRHANDLE));
closedir(DIRHANDLE);
- my $dfname;
- my $reqfile;
- foreach $dfname (sort @alldelayed) {
- $reqfile = "$path/$dfname";
- Debug(4, "queueing ".$reqfile);
+ foreach my $dfname (sort(@alldelayed)) {
+ my $reqfile = "$path/$dfname";
+ my ($host_id) = ($dfname =~ /\.([^.]*)$/);
+ Debug(4, "queueing ".$reqfile." for $host_id");
my $Handle = IO::File->new($reqfile);
my $cmd = <$Handle>;
chomp $cmd; # There may or may not be a newline...
$cmd = $cmd."\n"; # now for sure there's exactly one newline.
- my $Transaction = LondTransaction->new($cmd);
+ my $Transaction = LondTransaction->new("sethost:$host_id:$cmd");
$Transaction->SetDeferred($reqfile);
QueueTransaction($Transaction);
}
@@ -1150,7 +1224,7 @@ sub MakeLondConnection {
#
my $Socket = $Connection->GetSocket();
if($Socket eq undef) {
- die "did not get a socket from the connection";
+ &child_exit(-1, "did not get a socket from the connection");
} else {
&Debug(9,"MakeLondConnection got socket: ".$Socket);
}
@@ -1163,7 +1237,9 @@ sub MakeLondConnection {
data => $Connection,
desc => 'Connection to lond server');
$ActiveConnections{$Connection} = $event;
-
+ if ($ConnectionCount == 0) {
+ &SetupTimer; # Need to handle timeouts with connections...
+ }
$ConnectionCount++;
Debug(4, "Connection count = ".$ConnectionCount);
if($ConnectionCount == 1) { # First Connection:
@@ -1171,6 +1247,7 @@ sub MakeLondConnection {
}
Log("SUCESS", "Created connection ".$ConnectionCount
." to host ".GetServerHost());
+ $LondConnecting = 1; # Connection in progress.
return 1; # Return success.
}
@@ -1202,8 +1279,8 @@ The text of the request to send.
=cut
sub StartRequest {
- my $Lond = shift;
- my $Request = shift; # This is a LondTransaction.
+
+ my ($Lond, $Request) = @_;
Debug(6, "StartRequest: ".$Request->getRequest());
@@ -1254,15 +1331,20 @@ sub QueueTransaction {
if(!defined $LondSocket) { # Need to queue request.
Debug(5,"Must queue...");
$WorkQueue->enqueue($requestData);
- if($ConnectionCount < $MaxConnectionCount) {
+ Debug(5, "Queue Transaction startnew $ConnectionCount $LondConnecting");
+ if(($ConnectionCount < $MaxConnectionCount) && (! $LondConnecting)) {
+
if($ConnectionRetriesLeft > 0) {
Debug(5,"Starting additional lond connection");
- if(MakeLondConnection() == 0) {
+ if(&MakeLondConnection() == 0) {
EmptyQueue(); # Fail transactions, can't make connection.
+ CloseAllLondConnections; # Should all be closed but...
}
} else {
ShowStatus(GetServerHost()." >>> DEAD !!!! <<<");
+ $LondConnecting = 0;
EmptyQueue(); # It's worse than that ... he's dead Jim.
+ CloseAllLondConnections; # Should all be closed but..
}
}
} else { # Can start the request:
@@ -1305,7 +1387,7 @@ sub ClientRequest {
Debug(8,"Data: ".$data." this read: ".$thisread);
$data = $data.$thisread; # Append new data.
$watcher->data($data);
- if($data =~ /(.*\n)/) { # Request entirely read.
+ if($data =~ /\n$/) { # Request entirely read.
if($data eq "close_connection_exit\n") {
Log("CRITICAL",
"Request Close Connection ... exiting");
@@ -1313,6 +1395,9 @@ sub ClientRequest {
exit;
}
Debug(8, "Complete transaction received: ".$data);
+ if($LogTransactions) {
+ Log("SUCCESS", "Transaction: '$data'"); # Transaction has \n.
+ }
my $Transaction = LondTransaction->new($data);
$Transaction->SetClient($socket);
QueueTransaction($Transaction);
@@ -1321,6 +1406,40 @@ sub ClientRequest {
}
+#
+# Accept a connection request for a client (lonc child) and
+# start up an event watcher to keep an eye on input from that
+# Event. This can be called both from NewClient and from
+# ChildProcess if we are started in DieWhenIdle mode.
+# Parameters:
+# $socket - The listener socket.
+# Returns:
+# NONE
+# Side Effects:
+# An event is made to watch the accepted connection.
+# Active clients hash is updated to reflect the new connection.
+# The client connection count is incremented.
+#
+sub accept_client {
+ my ($socket) = @_;
+
+ Debug(8, "Entering accept for lonc UNIX socket\n");
+ my $connection = $socket->accept(); # Accept the client connection.
+ Debug(8,"Connection request accepted from "
+ .GetPeername($connection, AF_UNIX));
+
+
+ my $description = sprintf("Connection to lonc client %d",
+ $ClientConnection);
+ Debug(9, "Creating event named: ".$description);
+ Event->io(cb => \&ClientRequest,
+ poll => 'r',
+ desc => $description,
+ data => "",
+ fd => $connection);
+ $ActiveClients{$connection} = $ClientConnection;
+ $ClientConnection++;
+}
=pod
@@ -1339,21 +1458,8 @@ sub NewClient {
my $event = shift; # Get the event parameters.
my $watcher = $event->w;
my $socket = $watcher->fd; # Get the event' socket.
- my $connection = $socket->accept(); # Accept the client connection.
- Debug(8,"Connection request accepted from "
- .GetPeername($connection, AF_UNIX));
-
- my $description = sprintf("Connection to lonc client %d",
- $ClientConnection);
- Debug(9, "Creating event named: ".$description);
- Event->io(cb => \&ClientRequest,
- poll => 'r',
- desc => $description,
- data => "",
- fd => $connection);
- $ActiveClients{$connection} = $ClientConnection;
- $ClientConnection++;
+ &accept_client($socket);
}
=pod
@@ -1363,10 +1469,20 @@ sub NewClient {
Returns the name of the UNIX socket on which to listen for client
connections.
+=head2 Parameters:
+
+ host (optional) - Name of the host socket to return.. defaults to
+ the return from GetServerHost().
+
=cut
sub GetLoncSocketPath {
- return $UnixSocketDir."/".GetServerHost();
+
+ my $host = GetServerHost(); # Default host.
+ if (@_) {
+ ($host) = @_; # Override if supplied.
+ }
+ return $UnixSocketDir."/".$host;
}
=pod
@@ -1403,22 +1519,50 @@ connection. The event handler establish
(creating a communcations channel), that int turn will establish
another event handler to subess requests.
+=head2 Parameters:
+
+ host (optional) Name of the host to set up a unix socket to.
+
=cut
sub SetupLoncListener {
+ my $host = GetServerHost(); # Default host.
+ if (@_) {
+ ($host) = @_ # Override host with parameter.
+ }
+
my $socket;
- my $SocketName = GetLoncSocketPath();
+ my $SocketName = GetLoncSocketPath($host);
unlink($SocketName);
unless ($socket =IO::Socket::UNIX->new(Local => $SocketName,
- Listen => 10,
+ Listen => 250,
Type => SOCK_STREAM)) {
- die "Failed to create a lonc listner socket";
+ if($I_am_child) {
+ &child_exit(-1, "Failed to create a lonc listener socket");
+ } else {
+ die "Failed to create a lonc listner socket";
+ }
+ }
+ return $socket;
+}
+
+#
+# Toggle transaction logging.
+# Implicit inputs:
+# LogTransactions
+# Implicit Outputs:
+# LogTransactions
+sub ToggleTransactionLogging {
+ print STDERR "Toggle transaction logging...\n";
+ if(!$LogTransactions) {
+ $LogTransactions = 1;
+ } else {
+ $LogTransactions = 0;
}
- Event->io(cb => \&NewClient,
- poll => 'r',
- desc => 'Lonc listener Unix Socket',
- fd => $socket);
+
+
+ Log("SUCCESS", "Toggled transaction logging: $LogTransactions \n");
}
=pod
@@ -1430,17 +1574,40 @@ into the status file.
We also use this to reset the retries count in order to allow the
client to retry connections with a previously dead server.
+
=cut
+
sub ChildStatus {
my $event = shift;
my $watcher = $event->w;
Debug(2, "Reporting child status because : ".$watcher->data);
my $docdir = $perlvar{'lonDocRoot'};
- my $fh = IO::File->new(">>$docdir/lon-status/loncstatus.txt");
- print $fh $$."\t".$RemoteHost."\t".$Status."\t".
+
+ open(LOG,">>$docdir/lon-status/loncstatus.txt");
+ flock(LOG,LOCK_EX);
+ print LOG $$."\t".$RemoteHost."\t".$Status."\t".
$RecentLogEntry."\n";
+ #
+ # Write out information about each of the connections:
+ #
+ if ($DebugLevel > 2) {
+ print LOG "Active connection statuses: \n";
+ my $i = 1;
+ print STDERR "================================= Socket Status Dump:\n";
+ foreach my $item (keys %ActiveConnections) {
+ my $Socket = $ActiveConnections{$item}->data;
+ my $state = $Socket->GetState();
+ print LOG "Connection $i State: $state\n";
+ print STDERR "---------------------- Connection $i \n";
+ $Socket->Dump(-1); # Ensure it gets dumped..
+ $i++;
+ }
+ }
+ flock(LOG,LOCK_UN);
+ close(LOG);
$ConnectionRetriesLeft = $ConnectionRetries;
+ UpdateStatus();
}
=pod
@@ -1461,12 +1628,14 @@ sub SignalledToDeath {
chomp($signal);
Log("CRITICAL", "Abnormal exit. Child $$ for $RemoteHost "
."died through "."\"$signal\"");
- LogPerm("F:lonc: $$ on $RemoteHost signalled to death: "
- ."\"$signal\"");
+ #LogPerm("F:lonc: $$ on $RemoteHost signalled to death: "
+# ."\"$signal\"");
exit 0;
}
+=pod
+
=head2 ToggleDebug
This sub toggles trace debugging on and off.
@@ -1482,18 +1651,54 @@ sub ToggleDebug {
}
+=pod
+
=head2 ChildProcess
This sub implements a child process for a single lonc daemon.
+Optional parameter:
+ $socket - if provided, this is a socket already open for listen
+ on the client socket. Otherwise, a new listen is set up.
=cut
sub ChildProcess {
+ # If we are in DieWhenIdle mode, we've inherited all the
+ # events of our parent and those have to be cancelled or else
+ # all holy bloody chaos will result.. trust me, I already made
+ # >that< mistake.
+
+ my $host = GetServerHost();
+ foreach my $listener (keys %parent_dispatchers) {
+ my $watcher = $parent_dispatchers{$listener};
+ my $s = $watcher->fd;
+ if ($listener ne $host) { # Close everyone but me.
+ Debug(5, "Closing listen socket for $listener");
+ $s->close();
+ }
+ Debug(5, "Killing watcher for $listener");
+
+ $watcher->cancel();
+ delete($parent_dispatchers{$listener});
+
+ }
+
+ # kill off the parent's signal handlers too!
+ #
+
+ for my $handler (keys %parent_handlers) {
+ my $watcher = $parent_handlers{$handler};
+ $watcher->cancel();
+ delete($parent_handlers{$handler});
+ }
+
+ $I_am_child = 1; # Seems like in spite of it all I may still getting
+ # parent event dispatches.. flag I'm a child.
#
# Signals must be handled by the Event framework...
-#
+ #
Event->signal(signal => "QUIT",
cb => \&SignalledToDeath,
@@ -1504,36 +1709,57 @@ sub ChildProcess {
Event->signal(signal => "USR1",
cb => \&ChildStatus,
data => "USR1");
+ Event->signal(signal => "USR2",
+ cb => \&ToggleTransactionLogging);
Event->signal(signal => "INT",
cb => \&ToggleDebug,
data => "INT");
- SetupTimer();
-
- SetupLoncListener();
+ # Figure out if we got passed a socket or need to open one to listen for
+ # client requests.
+
+ my ($socket) = @_;
+ if (!$socket) {
+
+ $socket = SetupLoncListener();
+ }
+ # Establish an event to listen for client connection requests.
+
+
+ Event->io(cb => \&NewClient,
+ poll => 'r',
+ desc => 'Lonc Listener Unix Socket',
+ fd => $socket);
- $Event::Debuglevel = $DebugLevel;
+ $Event::DebugLevel = $DebugLevel;
Debug(9, "Making initial lond connection for ".$RemoteHost);
# Setup the initial server connection:
- # &MakeLondConnection(); // let first work requirest do it.
+ # &MakeLondConnection(); // let first work request do it.
+ # If We are in diwhenidle, need to accept the connection since the
+ # event may not fire.
+
+ if ($DieWhenIdle) {
+ &accept_client($socket);
+ }
Debug(9,"Entering event loop");
my $ret = Event::loop(); # Start the main event loop.
- die "Main event loop exited!!!";
+ &child_exit (-1,"Main event loop exited!!!");
}
# Create a new child for host passed in:
sub CreateChild {
+ my ($host, $socket) = @_;
+
my $sigset = POSIX::SigSet->new(SIGINT);
sigprocmask(SIG_BLOCK, $sigset);
- my $host = shift;
$RemoteHost = $host;
Log("CRITICAL", "Forking server for ".$host);
my $pid = fork;
@@ -1547,10 +1773,157 @@ sub CreateChild {
ShowStatus("Connected to ".$RemoteHost);
$SIG{INT} = 'DEFAULT';
sigprocmask(SIG_UNBLOCK, $sigset);
- ChildProcess; # Does not return.
+ if(defined $socket) {
+ &ChildProcess($socket);
+ } else {
+ ChildProcess; # Does not return.
+ }
+ }
+}
+
+# parent_client_connection:
+# Event handler that processes client connections for the parent process.
+# This sub is called when the parent is listening on a socket and
+# a connection request arrives. We must:
+# Start a child process to accept the connection request.
+# Kill our listen on the socket.
+# Parameter:
+# event - The event object that was created to monitor this socket.
+# event->w->fd is the socket.
+# Returns:
+# NONE
+#
+sub parent_client_connection {
+ if ($I_am_child) {
+ # Should not get here, but seem to anyway:
+ &Debug(5," Child caught parent client connection event!!");
+ my ($event) = @_;
+ my $watcher = $event->w;
+ $watcher->cancel(); # Try to kill it off again!!
+ } else {
+ &Debug(9, "parent_client_connection");
+ my ($event) = @_;
+ my $watcher = $event->w;
+ my $socket = $watcher->fd;
+
+ # Lookup the host associated with this socket:
+
+ my $host = $listening_to{$socket};
+
+ # Start the child:
+
+
+
+ &Debug(9,"Creating child for $host (parent_client_connection)");
+ &CreateChild($host, $socket);
+
+ # Clean up the listen since now the child takes over until it exits.
+
+ $watcher->cancel(); # Nolonger listening to this event
+ delete($listening_to{$socket});
+ delete($parent_dispatchers{$host});
+ $socket->close();
+ }
+}
+
+# parent_listen:
+# Opens a socket and starts a listen for the parent process on a client UNIX
+# domain socket.
+#
+# This involves:
+# Creating a socket for listen.
+# Removing any socket lock file
+# Adding an event handler for this socket becoming readable
+# To the parent's event dispatcher.
+# Parameters:
+# loncapa_host - LonCAPA cluster name of the host represented by the client
+# socket.
+# Returns:
+# NONE
+#
+sub parent_listen {
+ my ($loncapa_host) = @_;
+ Debug(5, "parent_listen: $loncapa_host");
+
+ my $socket = &SetupLoncListener($loncapa_host);
+ $listening_to{$socket} = $loncapa_host;
+ if (!$socket) {
+ die "Unable to create a listen socket for $loncapa_host";
+ }
+
+ my $lock_file = &GetLoncSocketPath($loncapa_host).".lock";
+ unlink($lock_file); # No problem if it doesn't exist yet [startup e.g.]
+
+ my $watcher = Event->io(cb => \&parent_client_connection,
+ poll => 'r',
+ desc => "Parent listener unix socket ($loncapa_host)",
+ fd => $socket);
+ $parent_dispatchers{$loncapa_host} = $watcher;
+
+}
+
+
+# listen_on_all_unix_sockets:
+# This sub initiates a listen on all unix domain lonc client sockets.
+# This will be called in the case where we are trimming idle processes.
+# When idle processes are trimmed, loncnew starts up with no children,
+# and only spawns off children when a connection request occurs on the
+# client unix socket. The spawned child continues to run until it has
+# been idle a while at which point it eventually exits and once more
+# the parent picks up the listen.
+#
+# Parameters:
+# NONE
+# Implicit Inputs:
+# The configuration file that has been read in by LondConnection.
+# Returns:
+# NONE
+#
+sub listen_on_all_unix_sockets {
+ Debug(5, "listen_on_all_unix_sockets");
+ my $host_iterator = &LondConnection::GetHostIterator();
+ while (!$host_iterator->end()) {
+ my $host_entry_ref = $host_iterator->get();
+ my $host_name = $host_entry_ref->[3];
+ Debug(9, "Listen for $host_name");
+ &parent_listen($host_name);
+ $host_iterator->next();
+ }
+}
+
+# server_died is called whenever a child process exits.
+# Since this is dispatched via a signal, we must process all
+# dead children until there are no more left. The action
+# is to:
+# - Remove the child from the bookeeping hashes
+# - Re-establish a listen on the unix domain socket associated
+# with that host.
+# Parameters:
+# The event, but we don't actually care about it.
+sub server_died {
+ &Debug(9, "server_died called...");
+
+ while(1) { # Loop until waitpid nowait fails.
+ my $pid = waitpid(-1, WNOHANG);
+ if($pid <= 0) {
+ return; # Nothing left to wait for.
+ }
+ # need the host to restart:
+
+ my $host = $ChildHash{$pid};
+ if($host) { # It's for real...
+ &Debug(9, "Caught sigchild for $host");
+ delete($ChildHash{$pid});
+ delete($HostToPid{$host});
+ &parent_listen($host);
+
+ } else {
+ &Debug(5, "Caught sigchild for pid not in hosts hash: $pid");
+ }
}
}
+
#
# Parent process logic pass 1:
# For each entry in the hosts table, we will
@@ -1598,45 +1971,93 @@ ShowStatus("Forking node servers");
Log("CRITICAL", "--------------- Starting children ---------------");
+LondConnection::ReadConfig; # Read standard config files.
my $HostIterator = LondConnection::GetHostIterator;
-while (! $HostIterator->end()) {
- my $hostentryref = $HostIterator->get();
- CreateChild($hostentryref->[0]);
- $HostHash{$hostentryref->[0]} = $hostentryref->[4];
- $HostIterator->next();
+if ($DieWhenIdle) {
+ $RemoteHost = "[parent]";
+ &listen_on_all_unix_sockets();
+} else {
+
+ while (! $HostIterator->end()) {
+
+ my $hostentryref = $HostIterator->get();
+ CreateChild($hostentryref->[0]);
+ $HostHash{$hostentryref->[0]} = $hostentryref->[4];
+ $HostIterator->next();
+ }
}
+
$RemoteHost = "Parent Server";
# Maintain the population:
ShowStatus("Parent keeping the flock");
-#
-# Set up parent signals:
-#
-$SIG{INT} = \&Terminate;
-$SIG{TERM} = \&Terminate;
-$SIG{HUP} = \&Restart;
-$SIG{USR1} = \&CheckKids;
-$SIG{USR2} = \&UpdateKids; # LonManage update request.
-
-while(1) {
- my $deadchild = wait();
- if(exists $ChildHash{$deadchild}) { # need to restart.
- my $deadhost = $ChildHash{$deadchild};
- delete($HostToPid{$deadhost});
- delete($ChildHash{$deadchild});
- Log("WARNING","Lost child pid= ".$deadchild.
- "Connected to host ".$deadhost);
- Log("INFO", "Restarting child procesing ".$deadhost);
- CreateChild($deadhost);
+if ($DieWhenIdle) {
+ # We need to setup a SIGChild event to handle the exit (natural or otherwise)
+ # of the children.
+
+ Event->signal(cb => \&server_died,
+ desc => "Child exit handler",
+ signal => "CHLD");
+
+
+ # Set up all the other signals we set up. We'll vector them off to the
+ # same subs as we would for DieWhenIdle false and, if necessary, conditionalize
+ # the code there.
+
+ $parent_handlers{INT} = Event->signal(cb => \&Terminate,
+ desc => "Parent INT handler",
+ signal => "INT");
+ $parent_handlers{TERM} = Event->signal(cb => \&Terminate,
+ desc => "Parent TERM handler",
+ signal => "TERM");
+ $parent_handlers{HUP} = Event->signal(cb => \&Restart,
+ desc => "Parent HUP handler.",
+ signal => "HUP");
+ $parent_handlers{USR1} = Event->signal(cb => \&CheckKids,
+ desc => "Parent USR1 handler",
+ signal => "USR1");
+ $parent_handlers{USR2} = Event->signal(cb => \&UpdateKids,
+ desc => "Parent USR2 handler.",
+ signal => "USR2");
+
+ # Start procdesing events.
+
+ $Event::DebugLevel = $DebugLevel;
+ Debug(9, "Parent entering event loop");
+ my $ret = Event::loop();
+ die "Main Event loop exited: $ret";
+
+
+} else {
+ #
+ # Set up parent signals:
+ #
+
+ $SIG{INT} = \&Terminate;
+ $SIG{TERM} = \&Terminate;
+ $SIG{HUP} = \&Restart;
+ $SIG{USR1} = \&CheckKids;
+ $SIG{USR2} = \&UpdateKids; # LonManage update request.
+
+ while(1) {
+ my $deadchild = wait();
+ if(exists $ChildHash{$deadchild}) { # need to restart.
+ my $deadhost = $ChildHash{$deadchild};
+ delete($HostToPid{$deadhost});
+ delete($ChildHash{$deadchild});
+ Log("WARNING","Lost child pid= ".$deadchild.
+ "Connected to host ".$deadhost);
+ Log("INFO", "Restarting child procesing ".$deadhost);
+ CreateChild($deadhost);
+ }
}
}
-
=pod
=head1 CheckKids
@@ -1656,11 +2077,14 @@ sub CheckKids {
my $now=time;
my $local=localtime($now);
print $fh "LONC status $local - parent $$ \n\n";
+ foreach my $host (keys %parent_dispatchers) {
+ print $fh "LONC Parent process listening for $host\n";
+ }
foreach my $pid (keys %ChildHash) {
Debug(2, "Sending USR1 -> $pid");
kill 'USR1' => $pid; # Tell Child to report status.
- sleep 1; # Wait so file doesn't intermix.
}
+
}
=pod
@@ -1693,81 +2117,15 @@ sub UpdateKids {
Log("INFO", "Updating connections via SIGUSR2");
- # Just in case we need to kill our own lonc, we wait a few seconds to
- # give it a chance to receive and relay lond's response to the
- # re-init command.
- #
-
- sleep(2); # Wait a couple of seconds.
-
- my %hosts; # Indexed by loncapa hostname, value=ip.
-
- # Need to re-read the host table:
-
-
- LondConnection::ReadConfig();
- my $I = LondConnection::GetHostIterator;
- while (! $I->end()) {
- my $item = $I->get();
- $hosts{$item->[0]} = $item->[4];
- $I->next();
- }
-
- # The logic below is written for clarity not for efficiency.
- # Since I anticipate that this function is only rarely called, that's
- # appropriate. There are certainly ways to combine the loops below,
- # and anyone wishing to obscure the logic is welcome to go for it.
- # Note that we don't re-direct sigchild. Instead we do what's needed
- # to the data structures that keep track of children to ensure that
- # when sigchild is honored, no new child is born.
- #
+ # I'm not sure what I was thinking in the first implementation.
+ # someone will have to work hard to convince me the effect is any
+ # different than Restart, especially now that we don't start up
+ # per host servers automatically, may as well just restart.
+ # The down side is transactions that are in flight will get timed out
+ # (lost unless they are critical).
- # For each existing child; if it's host doesn't exist, kill the child.
-
- foreach my $child (keys %ChildHash) {
- my $oldhost = $ChildHash{$child};
- if (!(exists $hosts{$oldhost})) {
- Log("CRITICAL", "Killing child for $oldhost host no longer exists");
- delete $ChildHash{$child};
- delete $HostToPid{$oldhost};
- kill 'QUIT' => $child;
- }
- }
- # For each remaining existing child; if it's host's ip has changed,
- # Restart the child on the new IP.
-
- foreach my $child (keys %ChildHash) {
- my $oldhost = $ChildHash{$child};
- my $oldip = $HostHash{$oldhost};
- if ($hosts{$oldhost} ne $oldip) {
-
- # kill the old child.
-
- Log("CRITICAL", "Killing child for $oldhost host ip has changed...");
- delete $ChildHash{$child};
- delete $HostToPid{$oldhost};
- kill 'QUIT' => $child;
-
- # Do the book-keeping needed to start a new child on the
- # new ip.
-
- $HostHash{$oldhost} = $hosts{$oldhost};
- CreateChild($oldhost);
- }
- }
- # Finally, for each new host, not in the host hash, create a
- # enter the host and create a new child.
- # Force a status display of any existing process.
+ &Restart();
- foreach my $host (keys %hosts) {
- if(!(exists $HostHash{$host})) {
- Log("INFO", "New host $host discovered in hosts.tab...");
- $HostHash{$host} = $hosts{$host};
- CreateChild($host);
- } else {
- kill 'HUP' => $HostToPid{$host}; # status display.
- }
- }
}
@@ -1786,7 +2144,7 @@ sub Restart {
Log("CRITICAL", "Restarting");
my $execdir = $perlvar{'lonDaemons'};
unlink("$execdir/logs/lonc.pid");
- exec("$execdir/loncnew");
+ exec("$executable");
}
=pod
@@ -1803,17 +2161,34 @@ sub KillThemAll {
local($SIG{CHLD}) = 'IGNORE'; # Our children >will< die.
foreach my $pid (keys %ChildHash) {
my $serving = $ChildHash{$pid};
- Debug(2, "Killing lonc for $serving pid = $pid");
- ShowStatus("Killing lonc for $serving pid = $pid");
- Log("CRITICAL", "Killing lonc for $serving pid = $pid");
+ ShowStatus("Nicely Killing lonc for $serving pid = $pid");
+ Log("CRITICAL", "Nicely Killing lonc for $serving pid = $pid");
kill 'QUIT' => $pid;
- delete($ChildHash{$pid});
}
- my $execdir = $perlvar{'lonDaemons'};
- unlink("$execdir/logs/lonc.pid");
+
}
+
+#
+# Kill all children via KILL. Just in case the
+# first shot didn't get them.
+
+sub really_kill_them_all_dammit
+{
+ Debug(2, "Kill them all Dammit");
+ local($SIG{CHLD} = 'IGNORE'); # In case some purist reenabled them.
+ foreach my $pid (keys %ChildHash) {
+ my $serving = $ChildHash{$pid};
+ &ShowStatus("Nastily killing lonc for $serving pid = $pid");
+ Log("CRITICAL", "Nastily killing lonc for $serving pid = $pid");
+ kill 'KILL' => $pid;
+ delete($ChildHash{$pid});
+ my $execdir = $perlvar{'lonDaemons'};
+ unlink("$execdir/logs/lonc.pid");
+ }
+}
+
=pod
=head1 Terminate
@@ -1823,7 +2198,15 @@ Terminate the system.
=cut
sub Terminate {
- KillThemAll;
+ &Log("CRITICAL", "Asked to kill children.. first be nice...");
+ &KillThemAll;
+ #
+ # By now they really should all be dead.. but just in case
+ # send them all SIGKILL's after a bit of waiting:
+
+ sleep(4);
+ &Log("CRITICAL", "Now kill children nasty");
+ &really_kill_them_all_dammit;
Log("CRITICAL","Master process exiting");
exit 0;