in reply to Create based on repeating data

Like this?:

#! perl -slw
use strict;
use Data::Dump qw[ pp ];

my( %data, %subhash, $last );
while( <DATA> ) {
    if( /^H/ ) {
        if( $last ) {
            $data{ $last } = { %subhash };
           undef %subhash;
       }
        ( $last, my( $key, $val ) ) = m[(\S+)\s+(.+)\s+(\S+)$];
        $subhash{ $key } = $val;
    }
    else {
        my( $key, $val ) = m[^\s+(.+)\s+(\S+)$];
        $subhash{ $key } = $val;
    }
}
$data{ $last } = { %subhash };

pp \%data;

__DATA__
Hostname1     1.1.1.1     Cisco
              Chassis Serial Number xyz123
              Interface Gig0/0/31
Hostname2     2.2.2.2     Juniper
              Chassis Serial Number abc123
              Interface Gi-0/0/31

[download]

Outputs:

C:\test>1170268.pl
{
  Hostname1 => {
                 "1.1.1.1    " => "Cisco",
                 "Chassis Serial Number" => "xyz123",
                 Interface => "Gig0/0/31",
               },
  Hostname2 => {
                 "2.2.2.2    " => "Juniper",
                 "Chassis Serial Number" => "abc123",
                 Interface => "Gi-0/0/31",
               },
}

[download]
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Replies are listed 'Best First'.
Re^2: Create based on repeating data
by NetWallah (Canon) on Aug 24, 2016 at 03:21 UTC
    Avoiding the assumption that hostnames start with "H", and simplifying logic: 
    #! perl -slw
use strict;
use Data::Dumper;

my( @data, $current );
while( <DATA> ) {
    if( my ($host,$ip,$brand) =/^(\w+)\s+(\S+)\s+(\S+)/ ) {
        $current and push @data, $current;
        $current = {HOST=>$host, IP=>$ip, BRAND=>$brand};
        next;
    }
    my( $key, $val )  = m[\s+(.+)\s+(\S+)$] or next;
    $current->{$key} = $val;
}
$current and push @data, $current;

print Dumper \@data;

__DATA__
Hostname1     1.1.1.1     Cisco
              Chassis Serial Number xyz123
              Interface Gig0/0/31
Hostname2     2.2.2.2     Juniper
              Chassis Serial Number abc123
              Interface Gi-0/0/31

    [download]
    Output: 
    $VAR1 = [
          {
            'Chassis Serial Number' => 'xyz123',
            'Interface' => 'Gig0/0/31',
            'BRAND' => 'Cisco',
            'HOST' => 'Hostname1',
            'IP' => '1.1.1.1'
          },
          {
            'HOST' => 'Hostname2',
            'BRAND' => 'Juniper',
            'Chassis Serial Number' => 'abc123',
            'Interface' => 'Gi-0/0/31',
            'IP' => '2.2.2.2'
          }
        ];

    [download]
    Alternative, using hostname as a key to a hash: 
     my ($current,%data)
...
        $current and $data{$current->{HOST}} = $current; # in 2 places
        $current = {HOST=>$host, IP=>$ip, BRAND=>$brand};

    [download]

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