...But I'm looking for the host_name and address in addition to the line... 
#!/usr/bin/perl
use warnings;
use strict;
use Data::Dumper;

my %host_add;
my ( $host, $name );

while (<DATA>) {
    s/^\s+|\s+$//;
    if (/^host_name/) {
        ( $host, $name ) = split /\s+/, $_;
        if ( !exists $host_add{$name} ) {
            undef $host_add{$name};
        }
        else { next }
    }
    elsif ( /^address/ or /^hostgroups/ ) {
        my ( $add, $address ) = split /\s+/, $_;
        push @{ $host_add{$name} }, $address;
    }
}

print Dumper \%host_add;

__DATA__
define host{
   use                                  HALF
   host_name                      denlas02
   alias                                denlas02
   address                           146.xxx.xxx.xxx
   hostgroups                      LINUX,DEN,DMZ
}

define host{
        use                             HALF
        host_name                 ppplas11
        alias                            ppplas11
        address                       10.xxx.xxx.xxx
        hostgroups                 LINUX,PPO,ORAPRD
        }

define host{
        use                               ALIVE
        host_name                   ppplas12
        alias                              ppplas12
        address                        10.50.33.26
        hostgroups                   LINUX,GRID,RMAN,CRIT
        }

[download]
output 
$VAR1 = {
          'denlas02' => [
                          '146.xxx.xxx.xxx',
                          'LINUX,DEN,DMZ'
                        ],
          'ppplas11' => [
                          '10.xxx.xxx.xxx',
                          'LINUX,PPO,ORAPRD'
                        ],
          'ppplas12' => [
                          '10.50.33.26',
                          'LINUX,GRID,RMAN,CRIT'
                        ]
        };

[download]
With the above as output, you can get the host, hostgroup, and address..
Add the following to the script like so: 
 for my $val ( keys %host_add ) {
    for ( @{ $host_add{$val} } ) {
        print $val, q{ }, join " ", @{ $host_add{$val} }, $/
          if $_ =~ m{CRIT|DMZ};
    }
}

[download]
Then, your output will be:
denlas02 146.xxx.xxx.xxx LINUX,DEN,DMZ 
ppplas12 10.50.33.26 LINUX,GRID,RMAN,CRIT

[download]
If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me

In reply to Re: split file on blank lines and match blocks by 2teez
in thread split file on blank lines and match blocks by raggmopp

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