I forgot to mention in my previous post that the if (pat1) {} elsif (pat2) {} elsif ... inside a while loop method is useful when data records is not always in the same order.

In this case, where your "output" format is fixed, it's better (faster) to use a per line parsing method (no while):

#!perl

use strict;
use warnings;
use Data::Dumper;

my %hash = ();

$_ = <DATA>;
/:\s(.*?)\s+\w+\s+:\s(.*?)\s*$/;
$hash{'VLAN'} = $1;
$hash{'STAT'} = $2;
$_ = <DATA>;
/:\s(.*?)\s+\w+\s+:\s(.*?)\s*$/;
$hash{'FID'} = $1;
$hash{'NAME'} = $2;
$_ = <DATA>;
/:\s(.*?)\s+\w+\s\w+:\s(.*?)\s*$/;
$hash{'VTYPE'} = $1;
$hash{'LASTM'} = $2;
$_ = <DATA>;
$_ = <DATA>;
/^\s*(.*?)\s*$/;
$hash{'EP'} = $1;
$_ = <DATA>;
$_ = <DATA>;
/^\s*(.*?)\s*$/;
$hash{'FEP'} = $1;
$_ = <DATA>;
$_ = <DATA>;
/^\s*(.*?)\s*$/;
$hash{'UP'} = $1;

print Dumper( \%hash );

__DATA__
VLAN     : 1           Status     : Enabled
FID      : 1           Name       : Some VLAN with    spaces
VLAN Type: Permanent   Last change: 2009-08-31 16:48:45
 Egress Ports:
host.0.1
 Forbidden Egress Ports:
ge.3.39
 Untagged Ports:
host.0.1
[download]

This way, you can control other things like key names:

$VAR1 = {
          'NAME' => 'Some VLAN with    spaces',
          'LASTM' => '2009-08-31 16:48:45',
          'VTYPE' => 'Permanent',
          'FID' => '1',
          'VLAN' => '1',
          'STAT' => 'Enabled',
          'UP' => 'host.0.1',
          'EP' => 'host.0.1',
          'FEP' => 'ge.3.39'
        };
[download]

Thinking a bit more on my first script, I realize that the string can be also modified in the following way: add a new delimiter just before what we detect as a field name (words separated by exactly one space, before any colon followed by a space), then split:

#!perl

use strict;
use warnings;
use Data::Dumper;

my $string = "";

while(<DATA>) {
    $_ =~ s/\n/  /g;
    $string .= $_;
}

$string =~ s/((\w+\s)*\w+)\s*:\s+/\%$1%/g;
$string =~ s/^\%(.*)/$1\%/;
$string =~ s/\s+\%/\%/g;

my %hash = split (/\%/, $string);

print Dumper( \%hash );

__DATA__
VLAN     : 1           Status     : Enabled
FID      : 1           Name       : Some VLAN with    spaces
VLAN Type: Permanent   Last change: 2009-08-31 16:48:45
 Egress Ports:
host.0.1
 Forbidden Egress Ports:
ge.3.39
 Untagged Ports:
host.0.1
[download]

$VAR1 = {
          'Last change' => '2009-08-31 16:48:45',
          'Status' => 'Enabled',
          'Forbidden Egress Ports' => 'ge.3.39',
          'FID' => '1',
          'VLAN' => '1',
          'Untagged Ports' => 'host.0.1',
          'Egress Ports' => 'host.0.1',
          'Name' => 'Some VLAN with    spaces',
          'VLAN Type' => 'Permanent'
        };
[download]

I also changed the delimiter to another unused char, to differentiate it from the colon inside the time value when trimming out extra spaces.

BTW, this was fun!