一年前搞的一套小脚本，今天翻博客发现没发过，现在发上来好了。主要背景是这样：考虑到有 DNS 和 HTTP 劫持需要监控，但是很多 DNS 服务器对非本区域本运营商的来源请求是拒绝做出响应的，所以得把监控点分散到各地去。其实做这个事情用 nagios 的分布式就足够了，不过如果想做即时触发的紧急任务，就算在 nagios 页面上点击立刻执行，到返回全部结果也得有一阵子。所以选择了自己写一套分布式的异步系统。
中控端脚本如下：
#!/usr/bin/perl
use Modern::Perl;
use AnyEvent;
use AnyEvent::Redis::RipeRedis;
use Storable qw/freeze thaw/;
use YAML::Syck;
use utf8;
my $area = $ARGV[0];
my $domain = 'fmn.xnimg.cn';
my $master = '10.4.1.21';
my $cv = AnyEvent->condvar;
my $redis = AnyEvent::Redis::RipeRedis->new(
host => $master,
port => 6379,
encoding => 'utf8',
);
my $dnslist = LoadFile("DNS.yml");
for my $isp ( sort keys %$dnslist ) {
if ( defined $area ) {
next unless defined $dnslist->{$isp}->{$area};
say $area, $isp, join ", ", @{ $dnslist->{$isp}->{$area} };
my $data = freeze({ domain => $domain, dnslist => $dnslist->{$isp}->{$area} });
$redis->publish( 'task', $data );
} else {
for my $list ( sort keys %{ $dnslist->{$isp} } ) {
my $data = freeze({ domain => $domain, dnslist => $dnslist->{$isp}->{$list} });
$cv->begin;
$redis->publish( 'task', $data );
}
}
}
$redis->subscribe(
qw( report ),
{
on_done => sub {
my $ch_name = shift;
my $subs_num = shift;
print "Subscribed: $ch_name. Active: $subs_num\n";
},
on_message => sub {
my $ch_name = shift;
my $msg = thaw( shift );
printf "%s A %s @%s in %s got %s length %s\n", $domain, $msg->{ip}, $msg->{dns}, $msg->{local}, $msg->{status}, $msg->{len};
$cv->end;
},
on_error => sub {
print @_;
},
}
);
$cv->recv;
分布在各地的客户端脚本如下：
#!/usr/bin/perl
use Modern::Perl;
use AnyEvent;
use AnyEvent::Socket;
use AnyEvent::DNS;
use AnyEvent::Redis::RipeRedis;
use AnyEvent::HTTP;
use Storable qw/freeze thaw/;
use Digest::MD5 qw/md5_hex/;
use utf8;
my $master = '10.4.1.21';
my $local = '192.168.0.2';
my $cv = AnyEvent->condvar;
my $redisr = AnyEvent::Redis::RipeRedis->new(
host => $master,
port => 6379,
encoding => 'utf8',
);
my $redisp = AnyEvent::Redis::RipeRedis->new(
host => $master,
port => 6379,
encoding => 'utf8',
);
$redisr->subscribe(
'task',
{
on_done => sub {
my $ch_name = shift;
my $subs_num = shift;
print "Subscribed: $ch_name. Active: $subs_num\n";
},
on_message => sub {
my $ch_name = shift;
my $msg = thaw(shift);
for my $dns ( @{ $msg->{dnslist} } ) {
resolv( $dns, $msg->{domain} );
}
},
on_error => sub {
my $err_msg = shift;
my $err_code = shift;
print "Error: ($err_code) $err_msg\n";
},
}
);
$cv->recv;
sub resolv {
my ( $dns, $domain ) = @_;
return unless $dns =~ m/^\d+/;
my $resolver =
AnyEvent::DNS->new( server => [ AnyEvent::Socket::parse_address $dns ], );
$resolver->resolve(
"$domain" => 'a',
sub {
httptest($dns, $domain, $_->[-1]) for @_;
}
);
}
sub httptest {
my ($dns, $domain, $ip) = @_;
my $url = "http://$domain/10k.html";
my $begin = time;
http_get $url, proxy => [$ip, 80], want_body_handle => 1, sub {
my ($hdl, $hdr) = @_;
my ($port, $peer) = AnyEvent::Socket::unpack_sockaddr getpeername $hdl->{'fh'};
my $data = freeze( { dns => $dns, status => $hdr->{Status}, local => $local, ip => $peer, len => $hdr->{'content-length'} } );
$redisp->publish('report', $data);
};
}
这里需要单独建立两个 $redisr 和 $redisp ，因为前一个已经用来 subscribe 之后就不能同时用于 publish 了，会报错。从理解上这是个很扯淡的事情，不过实际运行结果就是如此。。。
