Hi all. Working with perl 5.8.8 installed on OEL 5.

I am trying to parse a Nagios formatted hosts.cfg file. Each host is separated from the other with a blank line so there is a block related to each host. Each host is also defined with the hostgroups it is a member of.

I am having a hard time trying to figure out what I am missing and the worse part is I'm sober.

A snippet of the 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]

I have been trying and trying to identify hosts that are members of the CRIT hostgroup, or of the DMZ hostgroup, or the ... The best I have come up with is to print the line that matches. But I'm looking for the host_name and address in addition to the line.

One of my latest attempts

#!/usr/local/bin/perl
use strict;
use warnings;
my $file = 'hosts.cfg';
open (MYHOSTS, $file);
while (<MYHOSTS>) {
  my @hosts = split(/\n\n/);
  foreach my $host (@hosts) {
        print if ('$host' =~ m/(GRID)/);
        print if grep(/RMAN/, $host);
      }
}
close (MYHOSTS);

[download]

I've tried with grep and regex, no joy. What is it I'm missing?

Many thanks!

In reply to split file on blank lines and match blocks by raggmopp

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