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Francisco_30437's avatar
Francisco_30437
Icon for Nimbostratus rankNimbostratus
Jul 28, 2010

Configure Health Monitor for Netbios Name Server UDP/137 on F5 big-ip

Hello all,

 

 

I'm wondering if it's possible to configure a health monitor to check if a WINS server is active. Now I have configured a default udp monitor and when I stop the WINS service on the server, F5 doesn't detect anything, the server remains up in the pool and F5 still continue sending traffic to the server. This is because using default udp monitor, if F5 doesn't get any error reply, assumes the service is UP.

 

 

I have read info about external monitors for dns service but to use the same solution we need an application similar to nslookup or dig to send requests to WINS servers. Anyone knows a netbios client for F5 big-ip?

 

 

Thanks for your comments.

 

 

Francisco
microsoft
partner

2 Replies

  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jul 29, 2010
    Hi Francisco,

     

     

    Check your other post for more info:

     

     

    http://devcentral.f5.com/Community/GroupDetails/tabid/1082223/aff/25/afv/topic/aft/1172759/afc/1196771/Default.aspx

     

     

    Aaron
  • daniel_chien_18's avatar
    daniel_chien_18
    Historic F5 Account
    Jun 11, 2011
    For Microsoft WINS server monitor (Netbios name server), it may need to create an external monitor with perl script that queries Netbios name.

     

    1.Install the following Perl code from CPAN to /usr/lib/perl5/site_perl/5.8.8/Net (BIG-IP LTM 10.x)

     

    Net::NBName http://search.cpan.org/~jmacfarla/Net-NBName-0.26/lib/Net/NBName.pm

     

    Net::Netmask http://search.cpan.org/dist/Net-Netmask/

     

    You may want to install on other CentOS system first and then copy over.

     

    2.Create a perl script in /usr/bin/monitors

     

     

    !/usr/bin/perl

     

    use strict;

     

    use Net::NBName;

     

    my $nb = Net::NBName->new;

     

    my $host = shift;

     

    my $port = shift;

     

    my $param = shift;

     

    $host =~ s/::ffff://;

     

     

    if ($param =~ /^([\w-]+)\(\w{1,2})$/) {

     

    my $name = $1;

     

    my $suffix = hex $2;

     

    my $nq;

     

    if (defined($host) && $host =~ /\d+\.\d+\.\d+\.\d+/) {

     

    printf "querying %s for %s<%02X>...\n", $host, $name, $suffix;

     

    $nq = $nb->name_query($host, $name, $suffix);

     

    } else {

     

    printf "broadcasting for %s<%02X>...\n", $name, $suffix;

     

    $nq = $nb->name_query(undef, $name, $suffix);

     

    }

     

    if ($nq) {

     

    print $nq->as_string;

     

    print "UP\n";

     

    }

     

    }

     

     

    3.Create an external monitor. The external Program is the perl script created above. The Arguments is the netbios name you want to query. The format is netbios_namesuffix. You can find by “nbtstat –n” on the WINS server. For example, for domain name, it is domain_name00

     

     

    Daniel